Add Shoulda Matchers 3 configuration
Add Shoulda Matchers 3 configuration

From version 3.0.0 it is needed to specfied which test framework you're
using and which portion of the matchers you want to use in
`rails_helper.rb` (or the old `spec_helper.rb` in our case).

rishabhptr/osem,differentreality/osem,AndrewKvalheim/osem,openSUSE/osem,SeaGL/osem,rishabhptr/osem,openSUSE/osem,AndrewKvalheim/osem,hennevogel/osem,openSUSE/osem,rishabhptr/osem,SeaGL/osem,differentreality/osem,hennevogel/osem,SeaGL/osem,AndrewKvalheim/osem,hennevogel/osem,differentreality/osem,rishabhptr/osem,hennevogel/osem,differentreality/osem