doc: unify terminology to Standard library

This aligns the existing release notes with the upcoming release notes for Go
1.24 and newer (https://go.dev/cl/556817).

The term Standard library is more common, both in spoken and written
communication about Go. Also, it is engrained in commands like
go test std, which is not going to change.

Change-Id: I5cc2bfc608effe40befa8f168b1f08b9882ce7dd
Reviewed-on: https://go-review.googlesource.com/c/website/+/598096
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
diff --git a/_content/doc/go1.10.md b/_content/doc/go1.10.md
index 6fc1ebf..7feed25 100644
--- a/_content/doc/go1.10.md
+++ b/_content/doc/go1.10.md
@@ -509,7 +509,7 @@
 
 Many applications should experience significantly lower allocation latency and overall performance overhead when the garbage collector is active.
 
-## Core library {#library}
+## Standard library {#library}
 
 All of the changes to the standard library are minor.
 The changes in [bytes](#bytes)
diff --git a/_content/doc/go1.11.md b/_content/doc/go1.11.md
index 0995413..89d1cdf 100644
--- a/_content/doc/go1.11.md
+++ b/_content/doc/go1.11.md
@@ -394,7 +394,7 @@
 loops. Furthermore, the compiler now uses bounds information to more
 aggressively optimize shift operations.
 
-## Core library {#library}
+## Standard library {#library}
 
 All of the changes to the standard library are minor.
 
diff --git a/_content/doc/go1.12.md b/_content/doc/go1.12.md
index 4281d26..f28bb18 100644
--- a/_content/doc/go1.12.md
+++ b/_content/doc/go1.12.md
@@ -337,7 +337,7 @@
 during the initialization of a global variable will now show a
 function named `PKG.init.ializers`.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### TLS 1.3 {#tls_1_3}
 
diff --git a/_content/doc/go1.13.md b/_content/doc/go1.13.md
index e9e63bf..3a0ee5a 100644
--- a/_content/doc/go1.13.md
+++ b/_content/doc/go1.13.md
@@ -423,7 +423,7 @@
 Linux, the OS itself reclaims memory lazily, so process RSS will not
 decrease until the system is under memory pressure.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### TLS 1.3 {#tls_1_3}
 
diff --git a/_content/doc/go1.14.md b/_content/doc/go1.14.md
index 4a7b0b5..ba8976d 100644
--- a/_content/doc/go1.14.md
+++ b/_content/doc/go1.14.md
@@ -352,7 +352,7 @@
 Bounds check elimination now uses information from slice creation and can
 eliminate checks for indexes with types smaller than `int`.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### New byte sequence hashing package {#hash_maphash}
 
diff --git a/_content/doc/go1.15.md b/_content/doc/go1.15.md
index 2ea0b99..2a8afa0 100644
--- a/_content/doc/go1.15.md
+++ b/_content/doc/go1.15.md
@@ -315,7 +315,7 @@
 disassembling in GNU assembler syntax with the `-gnu`
 flag.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### New embedded tzdata package {#time_tzdata}
 
diff --git a/_content/doc/go1.16.md b/_content/doc/go1.16.md
index 2779e0a..762295c 100644
--- a/_content/doc/go1.16.md
+++ b/_content/doc/go1.16.md
@@ -423,7 +423,7 @@
 On Windows, `go build -buildmode=c-shared` now generates Windows
 ASLR DLLs by default. ASLR can be disabled with `--ldflags=-aslr=false`.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### Embedded Files {#library-embed}
 
diff --git a/_content/doc/go1.17.md b/_content/doc/go1.17.md
index 696bddc..ba02b63 100644
--- a/_content/doc/go1.17.md
+++ b/_content/doc/go1.17.md
@@ -432,7 +432,7 @@
 with a `-I` option, the option will now be passed to the
 external linker as a `-Wl,--dynamic-linker` option.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### [Cgo](/pkg/runtime/cgo) {#runtime_cgo}
 
diff --git a/_content/doc/go1.18.md b/_content/doc/go1.18.md
index 0220d82..be8d845 100644
--- a/_content/doc/go1.18.md
+++ b/_content/doc/go1.18.md
@@ -533,7 +533,7 @@
 and this change should make the transition smoother.
 For more details, see [go.dev/issue/44505](/issue/44505).
 
-## Core library {#library}
+## Standard library {#library}
 
 ### New `debug/buildinfo` package {#debug_buildinfo}
 
diff --git a/_content/doc/go1.19.md b/_content/doc/go1.19.md
index 89e6b75..ae72d59 100644
--- a/_content/doc/go1.19.md
+++ b/_content/doc/go1.19.md
@@ -266,7 +266,7 @@
 the standard gABI format (`SHF_COMPRESSED`), instead of
 the legacy `.zdebug` format.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### New atomic types {#atomic_types}
 
diff --git a/_content/doc/go1.20.md b/_content/doc/go1.20.md
index a760184..a4220e0 100644
--- a/_content/doc/go1.20.md
+++ b/_content/doc/go1.20.md
@@ -350,7 +350,7 @@
 In the future, we plan to move the bootstrap toolchain forward approximately once a year,
 and in particular we expect that Go 1.22 will require the final point release of Go 1.20 for bootstrap.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### New crypto/ecdh package {#crypto_ecdh}
 
diff --git a/_content/doc/go1.21.md b/_content/doc/go1.21.md
index 26d7076..71d66bc 100644
--- a/_content/doc/go1.21.md
+++ b/_content/doc/go1.21.md
@@ -306,7 +306,7 @@
 entries in the variable initializer is sufficiently large, and if the
 initializer expressions are side-effect free.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### New log/slog package {#slog}
 
diff --git a/_content/doc/go1.22.md b/_content/doc/go1.22.md
index 8b804f4..59c1efd 100644
--- a/_content/doc/go1.22.md
+++ b/_content/doc/go1.22.md
@@ -257,7 +257,7 @@
 the final point release of Go 1.20 or later for bootstrap.
 We expect that Go 1.24 will require the final point release of Go 1.22 or later for bootstrap.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### New math/rand/v2 package {#math_rand_v2}
 
diff --git a/_content/doc/go1.23.md b/_content/doc/go1.23.md
index 7491daf..9c7a72d 100644
--- a/_content/doc/go1.23.md
+++ b/_content/doc/go1.23.md
@@ -167,7 +167,7 @@
 When building a dynamically linked ELF binary (including PIE binary), the
 new `-bindnow` flag enables immediate function binding.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### Timer changes
 
diff --git a/_content/doc/go1.5.md b/_content/doc/go1.5.md
index a9865f0..9ce14e1 100644
--- a/_content/doc/go1.5.md
+++ b/_content/doc/go1.5.md
@@ -470,7 +470,7 @@
 For more details, see these [slides](/talks/2015/gogo.slide)
 and associated [video](https://www.youtube.com/watch?v=cF1zJYkBW4A).
 
-## Core library {#library}
+## Standard library {#library}
 
 ### Flag {#flag}
 
diff --git a/_content/doc/go1.6.md b/_content/doc/go1.6.md
index f21f3cc..91a8fc2 100644
--- a/_content/doc/go1.6.md
+++ b/_content/doc/go1.6.md
@@ -194,7 +194,7 @@
 [`crypto/ecdsa`](/pkg/crypto/ecdsa/), and
 [`sort`](/pkg/sort/) packages.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### HTTP/2 {#http2}
 
diff --git a/_content/doc/go1.7.md b/_content/doc/go1.7.md
index 7f4d652..8a85d52 100644
--- a/_content/doc/go1.7.md
+++ b/_content/doc/go1.7.md
@@ -304,7 +304,7 @@
 were in Go 1.6 for programs with large numbers of idle goroutines,
 substantial stack size fluctuation, or large package-level variables.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### Context {#context}
 
diff --git a/_content/doc/go1.9.md b/_content/doc/go1.9.md
index e07b61e..076fed3 100644
--- a/_content/doc/go1.9.md
+++ b/_content/doc/go1.9.md
@@ -305,7 +305,7 @@
 The [`runtime.ReadMemStats`](/pkg/runtime/#ReadMemStats)
 function now takes less than 100µs even for very large heaps.
 
-## Core library {#library}
+## Standard library {#library}
 
 ### Transparent Monotonic Time support {#monotonic-time}