runtime: speedup malloc stats collection
Count only number of frees, everything else is derivable
and does not need to be counted on every malloc.
benchmark                    old ns/op    new ns/op    delta
BenchmarkMalloc8                    68           66   -3.07%
BenchmarkMalloc16                   75           70   -6.48%
BenchmarkMallocTypeInfo8           102           97   -4.80%
BenchmarkMallocTypeInfo16          108          105   -2.78%

R=golang-dev, dave, rsc
CC=golang-dev
https://codereview.appspot.com/9776043
runtime: remove unused field from Hchan
Remove alignment logic as well, it's not respected by chanbuf() anyway.

R=golang-dev, dave, minux.ma, r, iant, rsc
CC=golang-dev
https://codereview.appspot.com/9678046
godoc: always use local jQuery script

Fixes issue 5075.

R=golang-dev, dsymonds
CC=golang-dev
https://codereview.appspot.com/10084044
runtime: remove unused mid function

R=golang-dev, r
CC=golang-dev
https://codereview.appspot.com/10036047
cmd/go: update go vet documentation

R=rsc, minux.ma, r
CC=golang-dev
https://codereview.appspot.com/10110043
all: fix typos

R=golang-dev, bradfitz, khr, r
CC=golang-dev
https://codereview.appspot.com/7461046
misc/pprof: fix html5 doctype declaration

R=golang-dev, bradfitz
CC=golang-dev
https://codereview.appspot.com/10099045
runtime: remove unused file mkversion.c

R=golang-dev, iant
CC=golang-dev
https://codereview.appspot.com/10107044
cmd/cgo: use gcc_struct attribute for packed structs to work around GCC PR52991.
Fixes issue 5603.

R=iant, dave
CC=gobot, golang-dev
https://codereview.appspot.com/9895043
doc/install-source.html: recent ARM and 386 updates

R=golang-dev, dave, adg, remyoudompheng, r
CC=golang-dev
https://codereview.appspot.com/6845083
runtime: use persistentalloc instead of custom malloc in memory profiler
Removes code duplication.

R=golang-dev, bradfitz
CC=golang-dev
https://codereview.appspot.com/9874055
runtime: use persistentalloc instead of SysAlloc in netpoll
Especially important for Windows because it reserves VM
only in multiple of 64k.

R=golang-dev, bradfitz
CC=golang-dev
https://codereview.appspot.com/10138043
runtime: use persistentalloc instead of mallocgc for itab
Reduces heap size.

R=golang-dev, remyoudompheng, bradfitz
CC=golang-dev
https://codereview.appspot.com/10139043
Merge branch 'master' into gitfix