content: fix stale links to line numbers

- Changed the links from go1.3 to master.
- Removed trailing spaces from several lines.

Fixes golang/go#22488

Change-Id: I41748fea956f0329eca0d520134670fa28618657
Reviewed-on: https://go-review.googlesource.com/86095
Reviewed-by: Andrew Bonventre <andybons@golang.org>
Reviewed-by: Kevin Burke <kev@inburke.com>
diff --git a/content/godoc-documenting-go-code.article b/content/godoc-documenting-go-code.article
index 05f5b1d..13df471 100644
--- a/content/godoc-documenting-go-code.article
+++ b/content/godoc-documenting-go-code.article
@@ -10,7 +10,7 @@
 
 To that end, we have developed the [[http://golang.org/cmd/godoc/][godoc]] documentation tool. This article describes godoc's approach to documentation, and explains how you can use our conventions and tools to write good documentation for your own projects.
 
-Godoc parses Go source code - including comments - and produces documentation as HTML or plain text. The end result is documentation tightly coupled with the code it documents. For example, through godoc's web interface you can navigate from a function's [[http://golang.org/pkg/strings/#HasPrefix][documentation]] to its [[http://golang.org/src/pkg/strings/strings.go?#L312][implementation]] with one click.
+Godoc parses Go source code - including comments - and produces documentation as HTML or plain text. The end result is documentation tightly coupled with the code it documents. For example, through godoc's web interface you can navigate from a function's [[http://golang.org/pkg/strings/#HasPrefix][documentation]] to its [[http://golang.org/src/pkg/strings/strings.go#L493][implementation]] with one click.
 
 Godoc is conceptually related to Python's [[http://www.python.org/dev/peps/pep-0257/][Docstring]] and Java's [[http://www.oracle.com/technetwork/java/javase/documentation/index-jsp-135444.html][Javadoc]], but its design is simpler. The comments read by godoc are not language constructs (as with Docstring) nor must they have their own machine-readable syntax (as with Javadoc). Godoc comments are just good comments, the sort you would want to read even if godoc didn't exist.
 
diff --git a/content/playground.article b/content/playground.article
index 1b3910b..02220b0 100644
--- a/content/playground.article
+++ b/content/playground.article
@@ -18,7 +18,7 @@
 
 You may also have used it by clicking one of the "Run" buttons in a slide
 deck on [[https://talks.golang.org/][talks.golang.org]] or a post on this
-very blog 
+very blog
 (such as the [[https://blog.golang.org/strings][recent article on Strings]]).
 
 In this article we will take a look at how the playground is implemented
@@ -46,7 +46,7 @@
 secure environment while still providing core functionality such as time, the
 network, and the file system.
 
-To isolate user programs from Google's infrastructure, the back end runs 
+To isolate user programs from Google's infrastructure, the back end runs
 them under [[https://developers.google.com/native-client/][Native Client]]
 (or "NaCl"), a technology developed by Google to permit the safe execution of
 x86 programs inside web browsers. The back end uses a special version of the gc
@@ -55,7 +55,7 @@
 (This special tool chain was merged into Go 1.3.
 To learn more, read the [[https://golang.org/s/go13nacl][design document]].)
 
-NaCl limits the amount of CPU and RAM a program may consume, and it prevents 
+NaCl limits the amount of CPU and RAM a program may consume, and it prevents
 programs from accessing the network or file system.
 This presents a problem, however.
 Go's concurrency and networking support are among its key strengths,
@@ -101,7 +101,7 @@
 sleeping goroutines.
 
 When a goroutine calls `time.Sleep` (or similar) the scheduler adds a timer to
-a heap of pending timers and puts the goroutine to sleep.  
+a heap of pending timers and puts the goroutine to sleep.
 Meanwhile, a special timer goroutine manages that heap.
 When the timer goroutine starts it tells the scheduler to wake
 it when the next pending timer is ready to fire and then sleeps.
@@ -182,7 +182,7 @@
 Programs built with the Go's NaCl tool chain cannot access the local machine's
 file system. Instead, the `syscall` package's file-related functions
 (`Open`, `Read`, `Write`, and so on) operate on an in-memory file system
-that is implemented by the `syscall` package itself.  
+that is implemented by the `syscall` package itself.
 Since package `syscall` is the interface between the Go code and the operating
 system kernel, user programs see the file system exactly the same way as they
 would a real one.
@@ -205,17 +205,17 @@
 the Go Tour.
 
 The implementation can be found in the
-[[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/fs_nacl.go][`fs_nacl.go`]] and
-[[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/fd_nacl.go][`fd_nacl.go`]] files
+[[https://github.com/golang/go/blob/master/src/syscall/fs_nacl.go][`fs_nacl.go`]] and
+[[https://github.com/golang/go/blob/master/src/syscall/fd_nacl.go][`fd_nacl.go`]] files
 (which, by virtue of their `_nacl` suffix, are built into package `syscall` only
 when `GOOS` is set to `nacl`).
 
-The file system itself is represented by the 
-[[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/fs_nacl.go#L25][`fsys` struct]],
+The file system itself is represented by the
+[[https://github.com/golang/go/blob/master/src/syscall/fs_nacl.go#L26][`fsys` struct]],
 of which a global instance (named `fs`) is created during init time.
 The various file-related functions then operate on `fs` instead of making the
 actual system call.
-For instance, here is the [[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/fs_nacl.go#L467][`syscall.Open`]] function:
+For instance, here is the [[https://github.com/golang/go/blob/master/src/syscall/fs_nacl.go#L473][`syscall.Open`]] function:
 
 	func Open(path string, openmode int, perm uint32) (fd int, err error) {
 		fs.mu.Lock()
@@ -228,17 +228,17 @@
 	}
 
 File descriptors are tracked by a global slice named
-[[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/fd_nacl.go#L16][`files`]].
-Each file descriptor corresponds to a [[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/fd_nacl.go#L24][`file`]]
-and each `file` provides a value that implements the [[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/fd_nacl.go#L29][`fileImpl`]] interface.
+[[https://github.com/golang/go/blob/master/src/syscall/fd_nacl.go#L17][`files`]].
+Each file descriptor corresponds to a [[https://github.com/golang/go/blob/master/src/syscall/fd_nacl.go#L23][`file`]]
+and each `file` provides a value that implements the [[https://github.com/golang/go/blob/master/src/syscall/fd_nacl.go#L30][`fileImpl`]] interface.
 There are several implementations of the interface:
 
-- regular files and devices (such as `/dev/random`) are represented by [[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/fs_nacl.go#L57][`fsysFile`]],
-- standard input, output, and error are instances of [[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/fd_nacl.go#L215][`naclFile`]], which uses system calls to interact with the actual files (these are a playground program's only way to interact with the outside world),
+- regular files and devices (such as `/dev/random`) are represented by [[https://github.com/golang/go/blob/master/src/syscall/fs_nacl.go#L58][`fsysFile`]],
+- standard input, output, and error are instances of [[https://github.com/golang/go/blob/master/src/syscall/fd_nacl.go#L216][`naclFile`]], which uses system calls to interact with the actual files (these are a playground program's only way to interact with the outside world),
 - network sockets have their own implementation, discussed in the next section.
 
 
-** Faking the network 
+** Faking the network
 
 Like the file system, the playground's network stack is an in-process fake
 implemented by the `syscall` package. It permits playground projects to use
@@ -256,8 +256,8 @@
 file system. It must simulate read and write timeouts, different address types
 and protocols, and so on.
 
-The implementation can be found in [[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/net_nacl.go][`net_nacl.go`]].
-A good place to start reading is [[https://github.com/golang/go/blob/go1.3/src/pkg/syscall/net_nacl.go#L428][`netFile`]], the network socket implementation of the `fileImpl` interface.
+The implementation can be found in [[https://github.com/golang/go/blob/master/src/syscall/net_nacl.go][`net_nacl.go`]].
+A good place to start reading is [[https://github.com/golang/go/blob/master/src/syscall/net_nacl.go#L461][`netFile`]], the network socket implementation of the `fileImpl` interface.
 
 
 * The front end
@@ -289,24 +289,24 @@
 button, and so on) and communicating with the playground front end.
 
 This implementation is in the file
-[[https://github.com/golang/tools/blob/release-branch.go1.3/godoc/static/playground.js][`playground.js`]]
+[[https://github.com/golang/tools/blob/master/godoc/static/playground.js][`playground.js`]]
 in the `go.tools` repository, which can be imported from the
 [[https://godoc.org/golang.org/x/tools/godoc/static][`golang.org/x/tools/godoc/static`]] package.
 Some of it is clean and some is a bit crufty, as it is the result of
 consolidating several divergent implementations of the client code.
 
-The [[https://github.com/golang/tools/blob/release-branch.go1.3/godoc/static/playground.js#L226][`playground`]]
+The [[https://github.com/golang/tools/blob/master/godoc/static/playground.js#L227][`playground`]]
 function takes some HTML elements and turns them into an interactive
 playground widget. You should use this function if you want to put the
 playground on your own site (see 'Other clients' below).
 
-The [[https://github.com/golang/tools/blob/release-branch.go1.3/godoc/static/playground.js#L6][`Transport`]]
+The [[https://github.com/golang/tools/blob/master/godoc/static/playground.js#L6][`Transport`]]
 interface (not formally defined, this being JavaScript)
 abstracts the user interface from the means of talking to the web front end.
-[[https://github.com/golang/tools/blob/release-branch.go1.3/godoc/static/playground.js#L43][`HTTPTransport`]]
+[[https://github.com/golang/tools/blob/master/godoc/static/playground.js#L43][`HTTPTransport`]]
 is an implementation of `Transport` that speaks the HTTP-based protocol
-described earlier. 
-[[https://github.com/golang/tools/blob/release-branch.go1.3/godoc/static/playground.js#L115][`SocketTransport`]]
+described earlier.
+[[https://github.com/golang/tools/blob/master/godoc/static/playground.js#L115][`SocketTransport`]]
 is another implementation that speaks WebSocket (see 'Playing offline' below).
 
 To comply with the [[https://en.wikipedia.org/wiki/Same-origin_policy][same-origin policy]],