Disabled mandatory PGP signing on release
Minor version bump to 3.1.0.beta.2 alias RC2
Removed Gemfile.lock from repository

See http://yehudakatz.com/2010/12/16/clarifying-the-roles-of-the-gemspec-and-gemfile/
Moved from 'rubygems-tasks' stable to master

* Resolves issues with newer versions of Rubygems
Merge pull request #71 from arax/master

Minor changes in project files