Adds tests for Readdir and Readdirnames with different n
values.  No good way to inject faults during full reads,
though.

Also fixes bug report from fshahriar:
Readdir(0) wasn't behaving like Readdir(-1).

R=rsc, fshahriar
CC=golang-dev
https://golang.org/cl/4529092

Also adds Host header tests.

Fixes #1886

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4556063

Issue 1886 has details

R=golang-dev, willchan
CC=golang-dev
https://golang.org/cl/4527083

Fixes #1882.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/4556062

Fixes issue #1879.

Directives were not directly expanded, but since their
content ended up in makefiles, further expansion would
take place there.  This prevents such artifacts by
restricting the set of characters that may be used in
a directive value.

To build the list of safe characters I went through the
contents of /usr/lib/pkgconfig and extracted LDFLAGS
and CFLAGS information, so hopefully this is a
reasonable default to get started.

R=rsc
CC=golang-dev
https://golang.org/cl/4532092

Fixes #1888.

R=ken
CC=golang-dev
https://golang.org/cl/4515148

Fixes #1791.

R=rsc, r, r, iant
CC=golang-dev
https://golang.org/cl/4551046

Also put Weekly Snapshot History link on 'Contributing' page

Fixes #1885.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/4559049

Fixes #1511 again.

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/4527070

Fixes issue #1853.

R=golang-dev, mattn.jp, adg
CC=golang-dev
https://golang.org/cl/4550084

R=rsc
CC=golang-dev
https://golang.org/cl/4539084

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/4515142

R=rsc
CC=golang-dev
https://golang.org/cl/4515135

Incorporate refactoring and a regression test from https://golang.org/cl/4538090/

R=rsc, go.peter.90, imkrasin
CC=golang-dev, mirtchovski
https://golang.org/cl/4524070

R=r
CC=golang-dev
https://golang.org/cl/4532090

Fixes #1843.

R=rsc
CC=golang-dev
https://golang.org/cl/4535101

R=r, rsc
CC=golang-dev
https://golang.org/cl/4530069

Added corresponding tests.

R=rsc
CC=golang-dev
https://golang.org/cl/4560045

Added a new Framer to handle reading/writing Frames. This is necessary since we have to maintain a compression context across streams.

TODO:
* Separate the types and read/write routines into different files.
* Improve error handling.

R=bradfitz, rsc
CC=golang-dev
https://golang.org/cl/4503042

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/4552066

before/after:
binary.BenchmarkRead  200000     10860 ns/op
binary.BenchmarkRead  500000      2846 ns/op

R=rsc
CC=golang-dev
https://golang.org/cl/4547062

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/4550086

R=rsc
CC=golang-dev
https://golang.org/cl/4532089

This permits external packages implementing e.g.
FTP or gopher to register themselves with the
http.DefaultClient:

package ftp
func init() {
    http.DefaultTransport.RegisterProtocol("ftp", &ftp{})
}

Client code would look like:

import (
    _ "github.com/exampleuser/go/gopher"
    _ "github.com/exampleuser/go/ftp"
)

func main() {
    resp, err := http.Get("ftp://example.com/path.txt")
    ...
}

R=dsymonds, rsc
CC=golang-dev
https://golang.org/cl/4526077

... like encoding/hex. Same signatures.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4530070

Fixes #1872.

R=rsc
CC=golang-dev, lars.pensjo
https://golang.org/cl/4559046

R=r, rsc
CC=golang-dev
https://golang.org/cl/4538096

R=rsc
CC=golang-dev
https://golang.org/cl/4548058

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/4529087

Speeds up static fileserver, avoiding kernel/userspace copies.

Numbers: downloading 14 MB AppEngine Go SDK with ab (Apache Bench)
with 5 threads:

Before/after numbers:

CPU:
user    0m3.910s
sys     0m23.650s
->
user    0m0.720s
sys     0m4.890s

Time taken for tests:   8.906 seconds
->
Time taken for tests:   8.545 seconds

Percentage of the requests served within a certain time (ms)
50%     44
66%     45
75%     46
80%     46
90%     48
95%     51
98%     59
99%     71
100     74 (longest request)
->
50%     42
66%     43
75%     43
80%     44
90%     46
95%     57
98%     62
99%     63
100%    64 (longest request)

R=iant, gary.burd, rsc, bradfitz
CC=golang-dev
https://golang.org/cl/4543071

R=ken2
CC=golang-dev
https://golang.org/cl/4539086

Makes all.bash work after echo 4 >/proc/cpu/alignment,
which means kill the process on an unaligned access.

The default behavior on DreamPlug/GuruPlug/SheevaPlug
is to simulate an ARMv3 and just let the unaligned accesses
stop at the word boundary, resulting in all kinds of surprises.

Fixes #1240.

R=ken2
CC=golang-dev
https://golang.org/cl/4551064

R=ken2
CC=golang-dev
https://golang.org/cl/4538095

Reenable dwarf output on Mac.
Was writing headers but no actual dwarf data.

Fixes #1877 (accidentally).
Workaround for issue 1878.

R=lvd
CC=golang-dev
https://golang.org/cl/4515139

R=alex.brainman, rsc
CC=golang-dev, vcc.163
https://golang.org/cl/4516055

R=rsc
CC=golang-dev
https://golang.org/cl/4556060

On Solaris /bin is a symlink to /usr/bin, so running "pwd" in
the directory "/bin" prints out "/usr/bin".

R=rsc, r, bradfitz
CC=golang-dev
https://golang.org/cl/4559043

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4556059

Fixes #1876.

R=golang-dev, bradfitz, gri, r
CC=golang-dev
https://golang.org/cl/4538093

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/4536082