Build all commands at the same time

In Go it's much more efficient to build several commands in the same
`go build` because the build has to load most of the dependency tree
each time.  Roughly 50% on my machine:

Together (go1.2 on OS X):

    real  0m4.049s
    user  0m8.387s
    sys   0m2.766s

Separate:

    real  0m13.392s
    user  0m12.420s
    sys   0m6.882s
Remove cmd/ prefix on build-go.sh

Update places that depend on it.
Merge pull request #626 from smarterclayton/speed_up_build

Build all commands at the same time
bump(github.com/google/cadvisor/client): fb8fa5d9353549ad265462c9e99affe93a3d5a22
Merge pull request #624 from dchen1107/cadvisor

update cadvisor client package which includes my fix for #608
Build binaries using Go 1.3

Currently binaries are built using Go 1.2.2, which results
in larger binaries than those produced by newer versions of
Go. The Go source archive used for the build process is not
verified against its SHA1 hash.

Update the build-image Dockerfile to use Go 1.3 to build all
binaries, as a result binaries are now 20% - 30% smaller. The
Go source archive used for building binaries is now verified
against its SHA1 hash.
Merge pull request #633 from kelseyhightower/go1.3-build

Build binaries using Go 1.3
Fix hack/build-go.sh to work on all platforms

Currently the hack/build-go.sh build script does not work
on OS X 10.9.x systems. This changes reverts back to building
one binary via a for loop.
Merge pull request #637 from kelseyhightower/fix-build-go

Fix hack/build-go.sh to work on all platforms
integration: Fix multiple response.WriteHeader calls

The current integration tests do not return after delegating
HTTP requests, as a result an extra call to response.WriteHeader
is made for every request.

Fix the issue by returning after delegating HTTP requests.
Merge pull request #638 from kelseyhightower/fix_multiple_response_write_headers

integration: Fix multiple response.WriteHeader calls
Add go fuzzer in preparation for testing. Also gofmt a few files that needed it.