Merge pull request #638 from kelseyhightower/fix_multiple_response_write_headers

integration: Fix multiple response.WriteHeader calls
httplog: Improve test coverage
Merge pull request #644 from kelseyhightower/improve_httplog_test_coverage

httplog: Improve test coverage
kubecfg: improve tests around authentication

This change adds additional test coverage for the kubecfg
command. There is now a test for the case when the auth info
file does not exist. LoadAuthInfo tests have been refactored
to use table testing.
Add a sanity check for running etcd servers to the integration test script.
Use http.StatusInternalServerError instead of 500
Allow API_PORT to be changed via hack/local-up
Fix typo in README
Remove extra test flags from all commands

Currently all commands are being build with extra flags. The extra
flags appear because of a direct import of the testing package from
the fake_etcd_client.go source file.

Remove the direct import of the testing package. Add a tools.T
interface to support existing behavior. Also clean up two TODO items
by remove using of the expectError and expectNoError functions.

Fixes #579
Add go fuzzer in preparation for testing. Also gofmt a few files that needed it.
Merge pull request #652 from kelseyhightower/fix_readme_typo

Fix typo in README
Merge pull request #650 from smarterclayton/use_constant_code

Use http.StatusInternalServerError instead of 500
Merge pull request #645 from brendandburns/integration

Add a sanity check for existing etcd servers to the integration test script
Add TODOs, clean up, clarify comments, and add one more test.
Fixing typos
Merge pull request #658 from danmcp/fix_typos

Fixing typos
Fixing Typos
Merge pull request #660 from danmcp/fix_typos

Fixing Typos

Thanks for the fix.
Merge pull request #647 from kelseyhightower/fix_extra_test_flags

Remove extra test flags from all commands
Merge pull request #636 from kelseyhightower/load_auth_info_tests

kubecfg: improve tests around authentication