Updated gem dependencies.

See http://weblog.rubyonrails.org/2013/2/11/SEC-ANN-Rails-3-2-12-3-1-11-and-2-3-17-have-been-released/
Merge pull request #5 from snowstorm/update_gems

Updated gem dependencies.

See http://weblog.rubyonrails.org/2013/2/11/SEC-ANN-Rails-3-2-12-3-1-11-and-2-3-17-have-been-released/