Ignore Gemfile.lock
"When developing a gem, Do not check your Gemfile.lock into version
 control"
http://yehudakatz.com/2010/12/16/clarifying-the-roles-of-the-gemspec-and-gemfile/
Merge pull request #1 from morozovm/54bd6a558baa7a2837cb503186507aa416277f62

 Ignore Gemfile.lock