corrected roles factory to use name column
added basic cucumber and rspec tests for testing the user handling by devise, tests adopted from http://railsapps.github.io/tutorial-rails-devise-rspec-cucumber.html with no added functionality
Added validation to the role model: presence of and uniqueness of name
Implemented simple spec for role model testing for
 - successful creation of a role
 - prevention of duplicate roles
 - prevention of nameless roles
Merge branch 'feature/tests' into develop

basic tests for the devise user management and the role model are in place
cucumber features as well as unit tests for the sign in, sign up, sign out and edit action for users
as well as for the user model and the role model are currently passing.