Merge pull request #9 from joshlf13/master

Added benchmarks for all methods (focused on comparing implementations).
Updating README.md to talk about the new features in place
Update .travis.yml to include the race detector.
Remove tip
Don't use race detector yet.
Wrong comment type.
README.md updated to reflect changes to the API

I've updated the README to match the current API (code example now compiles). The last line with the superset is a bit messy. There may be a better way?
Merge pull request #13 from TimothyJones/master

README.md updated to reflect changes to the API
Removed defers in thread-safe code for performance reasons.

- Recent testing (http://lk4d4.darth.io/posts/defer/) has shown that defer
  incurs high overhead when compared to normal function calls. For this
  reason, all defered calls have been instead placed as normal calls
  just before the appropriate return statement. Benchmarking has shown
  that this gives a significant performance improvement (for details,
  run "go test -test.bench '.*'").