This is part one of a small set of CL's that aim to resolve
the outstanding TODOs relating to channel close and blocking
behavior.

Firstly, the hairy handling of assigning the peersId is now
done in one place. The cost of this change is the slightly
paradoxical construction of the partially created clientChan.

Secondly, by creating clientChan.stdin/out/err when the channel
is opened, the creation of consumers like tcpchan and Session
is simplified; they just have to wire themselves up to the
relevant readers/writers.

R=agl, gustav.paul, rsc
CC=golang-dev
https://golang.org/cl/5448073

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5437142

Fixes #2530.

R=golang-dev, agl
CC=golang-dev
https://golang.org/cl/5449101

This is a slight change to fmt's semantics, but means that if you use
%d to print an integer with a Stringable value, it will print as an integer.
This came up because Time.Month() couldn't cleanly print as an integer
rather than a name. Using %d on Stringables is silly anyway, so there
should be no effect outside the fmt tests.
As a mild bonus, certain recursive failures of String methods
will also be avoided this way.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/5453053

Fixes #2466.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/5451094

R=golang-dev, gri, adg, r
CC=golang-dev
https://golang.org/cl/5434098

All but 3 cases (in gcimporter.go and hixie.go)
are automatic conversions using gofix.

No attempt is made to use the new Append functions
even though there are definitely opportunities.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5447069

R=golang-dev, bradfitz, gri, r, agl
CC=golang-dev
https://golang.org/cl/5434095

Includes minimal change to gcimporter to keep it working,

R=rsc, gri
CC=golang-dev
https://golang.org/cl/5431046

R=ken2
CC=golang-dev
https://golang.org/cl/5437136

R=gri, r, gustavo, r
CC=golang-dev
https://golang.org/cl/5451099

Also change "Special conditions" to "Special cases" as in other functions.

R=rsc, golang-dev
CC=golang-dev
https://golang.org/cl/5440078

By converting array indices to uint8, they are automatically
constrained in the array range, and the binary AND with 0xff
is no longer needed anymore.

Before:  aes.BenchmarkEncrypt    363 ns/op
After:   aes.BenchmarkEncrypt    273 ns/op

R=golang-dev, gri, agl
CC=golang-dev, remy
https://golang.org/cl/5450084

Equality on structs will require arbitrary code for type equality,
so change algorithm in type data from uint8 to table pointer.
In the process, trim top-level map structure from
104/80 bytes (64-bit/32-bit) to 24/12.

Equality on structs will require being able to call code generated
by the Go compiler, and C code has no way to access Go return
values, so change the hash and equal algorithm functions to take
a pointer to a result instead of returning the result.

R=ken
CC=golang-dev
https://golang.org/cl/5453043

gobuilder: -commit mode for packages
gobuilder: cripple -package mode temporarily

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5450092

misc/dashboard: support unauthenticated GETs
misc/dashboard: add ?nukeonly=1 option to /buildtest

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5450091

R=dsymonds
CC=golang-dev
https://golang.org/cl/5451092

Fixes #2522.

R=golang-dev, bradfitz, alex.brainman
CC=golang-dev
https://golang.org/cl/5449084

R=ken2, ken
CC=golang-dev
https://golang.org/cl/5449072

R=ken2
CC=golang-dev
https://golang.org/cl/5434111

R=ken2
CC=golang-dev
https://golang.org/cl/5450071

R=golang-dev, bradfitz, gri
CC=golang-dev
https://golang.org/cl/5451079

R=gri
CC=golang-dev
https://golang.org/cl/5448086

R=ken2
CC=golang-dev
https://golang.org/cl/5450067

R=golang-dev, gri, r, r
CC=golang-dev
https://golang.org/cl/5449067

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/5449068

This has always been true, but we lost it from the spec
somewhere along the way, probably when we disallowed
the general 'pointer to anything sliceable' slice case.

R=gri
CC=golang-dev
https://golang.org/cl/5437121

R=ken2
CC=golang-dev
https://golang.org/cl/5440083

The special case in the spec is that you can take the
address of a composite literal using the & operator.

A composite literal is not, however, generally addressable,
and the slice operator requires an addressable argument,
so [3]int{1,2,3}[:] is invalid.  This tutorial code and one bug
report are the only places in the tree where it appears.

R=r, gri
CC=golang-dev
https://golang.org/cl/5437120

R=gri
CC=golang-dev
https://golang.org/cl/5451078

The SSH spec allows for the server to send a banner message to the client at any point during the authentication process. Currently the ssh client auth types all assume that the first response from the server after issuing a userAuthRequestMsg will be one of a couple of possible authentication success/failure messages. This means that client authentication breaks if the ssh server being connected to has a banner message configured.

This changeset refactors the noneAuth, passwordAuth and publickeyAuth types' auth() function and allows for msgUserAuthBanner during authentication.

R=golang-dev, rsc, dave, agl
CC=golang-dev
https://golang.org/cl/5432065

R=golang-dev
CC=golang-dev
https://golang.org/cl/5449063

For now a pair of socket options SOL_SOCKET and SO_BINDTODEVICE
is supported on Linux only. I'd like to demote BindToDevice API
to syscall level because it's Linux dependent one.

In the near future, probably we may have a bit more portable
API that using IPROTO_IP/IPV6 level socket options to specify,
identify an inbound, outbound IP interface on incoming, outgoing
UDP and raw IP packets.

R=cw, golang-dev
CC=golang-dev
https://golang.org/cl/5447071

Fixes #2517.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/5440079

R=golang-dev, dsymonds, r
CC=golang-dev
https://golang.org/cl/5451073

R=golang-dev, dsymonds, rsc
CC=golang-dev
https://golang.org/cl/5437113

cmd.exe implicitly looks in "." before consulting PATH.
LookPath should match this behavior.

R=alex.brainman, rsc
CC=golang-dev
https://golang.org/cl/5434093

I had the wrong idea when I wrote this.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/5437111

tree sets.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/5449062

Also ignore <head> tag after </head>.

Pass tests6.dat, test 0:
<!doctype html></head> <head>

| <!DOCTYPE html>
| <html>
|   <head>
|   " "
|   <body>

Also pass tests through test 6:
<body>
<div>

R=nigeltao
CC=golang-dev
https://golang.org/cl/5447064