encoding/gob: delete dead code.

R=golang-dev, rsc
CC=golang-dev
https://codereview.appspot.com/7834047
build: remove dead code

R=golang-dev, r
CC=golang-dev
https://codereview.appspot.com/7877045
cmd/vet: diagnose unreachable code

R=golang-dev, r
CC=golang-dev
https://codereview.appspot.com/7493048
cmd/gc: fix line number for 'missing return' in closure

R=ken2
CC=golang-dev
https://codereview.appspot.com/7838048
doc/go1.1.html: return requirements

R=golang-dev, rsc, jeremyjackins, gri
CC=golang-dev
https://codereview.appspot.com/7838045
spec: remove most §links for the now more common in-text links

Also:
- more consistenly use "xxx" statement rather than <code>xxx</code> statement
- fix/remove unnecessary links

R=golang-dev, r
CC=golang-dev
https://codereview.appspot.com/7821050
net: fix documentation for UnixAddr

Also simplifies ResolveUnixAddr.

R=golang-dev, dave, rsc, bradfitz
CC=golang-dev
https://codereview.appspot.com/7510047
doc/go1.1.html: blockprofile, method values, ListenUnixgram, etc.

R=golang-dev, gri
CC=golang-dev
https://codereview.appspot.com/7496051
doc/go1.1.html: fix broken links

R=golang-dev, r
CC=golang-dev
https://codereview.appspot.com/7834049
runtime: correct misplaced right brace in Linux SIGBUS handling

I'm not sure how to write a test for this.  The change in
behaviour is that if you somehow get a SIGBUS signal for an
address >= 0x1000, the program will now crash rather than
calling panic.  As far as I know, on x86 GNU/Linux, the only
way to get a SIGBUS (rather than a SIGSEGV) is to set the
stack pointer to an invalid value.

R=golang-dev, r
CC=golang-dev
https://codereview.appspot.com/7906045
runtime: remove declaration of non-existent function

R=golang-dev, gri
CC=golang-dev
https://codereview.appspot.com/7577049
net: support IPv6 scoped addressing zone

This CL provides IPv6 scoped addressing zone support as defined
in RFC 4007 for internet protocol family connection setups.

Follwoing types and functions allow a literal IPv6 address with
zone identifer as theirs parameter.

pkg net, func Dial(string, string) (Conn, error)
pkg net, func DialOpt(string, ...DialOption) (Conn, error)
pkg net, func DialTimeout(string, string, time.Duration) (Conn, error)
pkg net, func Listen(string, string) (Listener, error)
pkg net, func ListenPacket(string, string) (PacketConn, error)
pkg net, func ResolveIPAddr(string, string) (*IPAddr, error)
pkg net, func ResolveTCPAddr(string, string) (*TCPAddr, error)
pkg net, func ResolveUDPAddr(string, string) (*UDPAddr, error)
pkg net, type IPAddr struct, Zone string
pkg net, type TCPAddr struct, Zone string
pkg net, type UDPAddr struct, Zone string

Also follwoing methods return a literal IPv6 address with zone
identifier string if possible.

pkg net, method (*IPAddr) String() string
pkg net, method (*TCPAddr) String() string
pkg net, method (*UDPAddr) String() string

Fixes issue 4234.
Fixes issue 4501.
Update issue 5081.

R=rsc, iant
CC=golang-dev
https://codereview.appspot.com/6816116
net: use original raddr if getpeername fails

This CL updates CL 7511043;
- adds new test cases for both UDPConn and UnixConn,
- makes sure unnamed UnixAddr handling,
- replaces t.Errorf with t.Fatalf in sockname related test cases.

Fixes issue 3721 (again).
Fixes issue 3838 (again).

R=golang-dev, rsc
CC=golang-dev
https://codereview.appspot.com/7627048
doc/go1.1.html: performance
An overview is all that's required.

R=golang-dev, remyoudompheng, bradfitz, adg
CC=golang-dev
https://codereview.appspot.com/7577050