Update ZenTest dependency to version 4.6.0
Update ZenTest dependency to version 4.6.0

sferik/sign-in-with-twitter,sferik/sign-in-with-twitter,arrogantgamer/ludum_dare_28,arrogantgamer/ludum_dare_28,theonlyjames/garbage,sferik/sign-in-with-twitter,theonlyjames/garbage,ksmetana/rails-app-twitter-test,ksmetana/rails-app-twitter-test