Test against ruby 2.1 and 2.2
Test against ruby 2.1 and 2.2

zlx/devise-two-factor,Momozono/Devise-Two-Factor-Test,ShaneWilton/devise-two-factor,tinfoil/devise-two-factor,zlx/devise-two-factor,Momozono/Devise-Two-Factor-Test,spanner/devise-two-factor,yann/devise-two-factor,dahal/devise-two-factor,yann/devise-two-factor,zlx/devise-two-factor,mo-zo/devise-two-factor,spanner/devise-two-factor,spanner/devise-two-factor,kesha-antonov/devise-two-factor,Momozono/Devise-Two-Factor-Test,civisanalytics/devise-two-factor,dahal/devise-two-factor,kesha-antonov/devise-two-factor,dahal/devise-two-factor,ShaneWilton/devise-two-factor,ShaneWilton/devise-two-factor,kesha-antonov/devise-two-factor,yann/devise-two-factor