Add note on how to build the jar and bundle
Add rake development dependency

This allows you to run:

    bundle exec rake

Before this change, this command failed with the error:
Gem::LoadError: rake is not part of the bundle. Add it to Gemfile.
Add Travis CI configuration file
Add Travis CI badge to the top of the README
Consistenly use double quotes in Rakefile
Cleanup trailing whitespace
Merge pull request #23 from sferik/travis-ci

Add Travis CI