GitHub master branch now targets Rails 4.2 and Ruby 2.0

[tvdeyen]

With the upcoming release of v3.1.0 we merged the rails-4.2 branch into the master.

So please update your Gemfiles to point to 3.1-stable branch if you still running on Rails 4.0 and Rails 4.1.

Use the master branch if you already running Rails 4.2 and used the now deleted rails-4.2 branch.

Please update your Ruby to 2.x if you are still running 1.9 (You seriously don't, aren't you?)

Keep on rocking \o/

<3