fmt: fix crash for Printf("%.", 3)
Fixes issue 5311

R=golang-dev, bradfitz, iant
CC=golang-dev
https://codereview.appspot.com/8961050
encoding/json: document that marshaling invalid utf-8 sequence will return error
Also added docs for InvalidUTF8Error.
Fixes issue 5360.

R=golang-dev, adg, r
CC=golang-dev
https://codereview.appspot.com/8926046
cmd/ld: fix some 64-bit issues
A few places in the linker pushed 64-bit values through 32-bit holes,
including in relocation.
Clean them up, and check for a few other overflows as well.
Tests to follow.

R=dsymonds
CC=gobot, golang-dev
https://codereview.appspot.com/9032043
cmd/gc: fix some overflows in the compiler
Some 64-bit fields were run through 32-bit words, some counts were
not checked for overflow, and relocations must fit in 32 bits.
Tests to follow.

R=golang-dev, dsymonds
CC=golang-dev
https://codereview.appspot.com/9033043
cmd/ld: disable relocation range check so build can go green while we debug the issue.

R=golang-dev, dsymonds, dave
CC=golang-dev
https://codereview.appspot.com/9038043
doc/go1.1: remove discussion of "go run" change

Update issue 5164

R=golang-dev, dave
CC=golang-dev
https://codereview.appspot.com/9049043
cmd/ld: fix check for address wrap in relocation
PC-relative needs a signed offset; others need unsigned.
Also fix signedness of 32-bit relocation on Windows.

R=golang-dev, iant
CC=golang-dev
https://codereview.appspot.com/9039045
cmd/ld: another attempt at the relocation overflow fix

R=golang-dev, iant
CC=golang-dev
https://codereview.appspot.com/9036046
syscall: fix exec_bsd.go to accompany exec_linux.go changes
exec_plan9.go too.
Those are in CL 8334044

R=golang-dev, iant
CC=golang-dev
https://codereview.appspot.com/9055043
syscall: fix a bug in the shuffling of file descriptors in StartProcess on Linux.

R=iant, iant, r, bradfitz
CC=golang-dev
https://codereview.appspot.com/8334044

Committer: Rob Pike <r@golang.org>
os/exec: disable TestExtraFilesFDShuffle
It's too hard to make portable just now.

R=golang-dev, iant
CC=golang-dev
https://codereview.appspot.com/9057043