all: link to https instead of http

The one in misc/makerelease/makerelease.go is particularly bad and
probably warrants rotating our keys.

I didn't update old weekly notes, and reverted some changes involving
test code for now, since we're late in the Go 1.5 freeze. Otherwise,
the rest are all auto-generated changes, and all manually reviewed.

Change-Id: Ia2753576ab5d64826a167d259f48a2f50508792d
Reviewed-on: https://go-review.googlesource.com/12048
Reviewed-by: Rob Pike <r@golang.org>
diff --git a/src/math/all_test.go b/src/math/all_test.go
index 6286584..0037b4a 100644
--- a/src/math/all_test.go
+++ b/src/math/all_test.go
@@ -2643,7 +2643,7 @@
 
 // Check that math constants are accepted by compiler
 // and have right value (assumes strconv.ParseFloat works).
-// http://golang.org/issue/201
+// https://golang.org/issue/201
 
 type floatTest struct {
 	val  interface{}