Add option to specify connection username.
Aliased :response accessor as :data
Updated README to reflect :user option
Added tests for Cpanel::Server#initialize :user key

  * Changed development dependency from thoughtbot-shoulda to shoulda.
  * Added development dependency for mocha (mocks used in unit tests).
Added Gemfile for Bundler
Merge pull request #1 from cblunt/master

Added option for username