Fixes #2821.

R=rsc
CC=golang-dev
https://golang.org/cl/5606061

Zip files may actually store symlinks, and that's represented
as a file with unix flag S_IFLNK and with its data containing
the symlink target name.

The other flags are being supported too. Now that the os package
has the full range of flags in a system agnostic manner, there's
no reason to discard that information.

R=golang-dev, adg, rogpeppe
CC=golang-dev
https://golang.org/cl/5624048

As pointed out in the discussion around 2678.

R=rsc
CC=golang-dev
https://golang.org/cl/5534077

since the real type is not inferred.
Fixes #2885.

R=golang-dev, dsymonds, bradfitz
CC=golang-dev
https://golang.org/cl/5633045

R=golang-dev
TBR=adg
CC=golang-dev, patrick
https://golang.org/cl/5616070

- fix documentation for NewBuffer and NewBufferString
- document and implement behavior of Truncate on invalid lengths

Fixes #2837.

R=rsc, adg
CC=golang-dev
https://golang.org/cl/5637044

- eliminate local Error type (a historical artifact)
- fix documentation of CopyN
- fix documentation of WriteString
Fixes #2859.

R=rsc, bradfitz
CC=golang-dev
https://golang.org/cl/5636046

      This fix makes the goFilesPackage helper function print the errors from
      package imports and exit similar to how the packagesForBuild function does.

      Without this change, when invoking "go build *.go" with, for example,
      an old import path, the following stack trace is generated:

      panic: runtime error: invalid memory address or nil pointer dereference

      goroutine 1 [running]:
      go/build.(*Tree).PkgDir(...)
              /opt/go/src/pkg/go/build/path.go:52 +0xfb
      main.(*builder).action(...)
              /opt/go/src/cmd/go/build.go:327 +0xb8
      main.(*builder).action(...)
              /opt/go/src/cmd/go/build.go:335 +0x208
      main.runBuild(...)
              /opt/go/src/cmd/go/build.go:129 +0x386
      main.main()
              /opt/go/src/cmd/go/main.go:126 +0x2d8

Fixes #2865.

R=rsc, dvyukov, r
CC=golang-dev
https://golang.org/cl/5624052

The practice encourages people to think this is the way to
create a bytes.Buffer when new(bytes.Buffer) or
just var buf bytes.Buffer work fine.
(html/token.go was missing the point altogether.)

R=golang-dev, bradfitz, r
CC=golang-dev
https://golang.org/cl/5637043

Fixes #2689.

R=r
CC=golang-dev
https://golang.org/cl/5616063

R=r
CC=golang-dev
https://golang.org/cl/5633044

Fixes #2857.

R=r, adg
CC=golang-dev
https://golang.org/cl/5635046

R=golang-dev, alex.brainman
CC=golang-dev
https://golang.org/cl/5631051

R=golang-dev, ality
CC=golang-dev
https://golang.org/cl/5636044

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5634045

rewrite the doc comment for Repeated.

Fixes #2858.

R=r, rsc
CC=golang-dev
https://golang.org/cl/5626050

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5624056

R=golang-dev, r, dsymonds, akumar
CC=golang-dev
https://golang.org/cl/5624054

R=rsc, balasanjay, rsc
CC=golang-dev
https://golang.org/cl/5630051

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5627051

clean.bash depends on it being set.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5630056

R=r
CC=golang-dev
https://golang.org/cl/5608061

Fixes #2772.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5631047

Thanks, Valgrind!

TBR=golang-dev
CC=golang-dev
https://golang.org/cl/5630050

5l does not use the whole set of ld files
like the other linkers do.

TBR=golang-dev
CC=golang-dev
https://golang.org/cl/5629052

Flush stdout before writing to stderr, to avoid
reordering output.

Allow amd64 from uname -m (FreeBSD).

TBR=golang-dev
CC=golang-dev
https://golang.org/cl/5629051

Should fix FreeBSD build.

TBR=golang-dev
CC=golang-dev
https://golang.org/cl/5629050

TBR=golang-dev
CC=golang-dev
https://golang.org/cl/5625050

TBR=golang-dev
CC=golang-dev
https://golang.org/cl/5630049

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5620059

R=bradfitz, ality, r, r, iant, mikioh.mikioh
CC=golang-dev
https://golang.org/cl/5615058

R=golang-dev, bradfitz, iant, alex.brainman, go.peter.90
CC=golang-dev
https://golang.org/cl/5630047

R=rsc, bradfitz
CC=golang-dev
https://golang.org/cl/5608060

Nuke RemoveAll from the public API.
Replace Iter functions with Do functions.

Fixes #2852.

R=rsc, r
CC=golang-dev
https://golang.org/cl/5622055

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5631044

The gccgo compiler was failing this test.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5631046

Fixes #2855.

R=r
CC=golang-dev
https://golang.org/cl/5608057

The gccgo compiler had two different bugs triggered by this
test case.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5606052

R=r
CC=golang-dev
https://golang.org/cl/5627048

goc2c moves here.
parallel builds like old makefiles (-j4).
add clean command.
add banner command.
implement Go version check.
real argument parsing (same as 6g etc)

Windows changes will be a separate CL.

R=golang-dev, bradfitz, iant
CC=golang-dev
https://golang.org/cl/5622058