Remove unused dependency upon `mocha`
Include `Gemfile.lock` in repository
Remove Ruby 1.9.3 from Travis CI testing matrix

`rubylines` does not yet support Ruby 1.9.3
Remove unnecessary Compass compilation settings
Refactor `Rakefile` to use `Compass.compiler` instead of loop
Refactor `unit_tests.rb` to use `Compass.compiler`
Merge pull request #53 from jamesreggio/2.x.x-testing

Improve unit testing framework