Darwin/amd64 now builds. No others tested yet.
mkall.sh also runs correctly. The updates, which are
substantial, are not yet applied to avoid unnecessary churn.
Restore mkerrors.sh, which is needed in the unix directory.

LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/122410044

Semi-automatic migration from package syscall to package {plan9,windows,unix}.
No builds attempted yet, but this gets a lot of noise behind us so subsequent
CLs will be more concise and easier to follow.
Subsequent CLs will have semantic content.

LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/121520043

This CL copies to each package of go.sys the files from syscall it will need.
Different directories have different files, but these:
        mkall.sh
        str.go
        syscall.go
        mksyscall.pl
        race.go
        race0.go
        syscall_test.go
are copied to all three.
No changes yet, these are just copies. They are not ready to use yet:
package names are wrong, for starters. But this clean copy will make
it easier to follow the changes as the packages are enabled.

LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/126960043

See http://golang.org/s/go1.4-syscall for background.

LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/123130043

R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/44810044

See this thread for background:
https://groups.google.com/forum/#!topic/golang-dev/xG7vPi21r8g

R=golang-codereviews, r
CC=golang-codereviews
https://golang.org/cl/39440047

I edited the wrong README when cloning the empty repo to create the tools one.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/9486043

This subrepo is the ultimate home for some of the experimental components
being developed in go.exp now, and also existing pieces such as go vet.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/9481043

R=r
CC=golang-dev
https://golang.org/cl/6026043

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5845057

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5572056