added devise at gemfile
deleted method of the old authentication
added views fo devise
test
Merge branch 'feature/add-devise' into develop
test
Merge branch 'revision' into develop
test
Merge branch 'revision2' into develop
deleted development.log
added configuration to loguin with twitter
added method twitter in controller
login failure by invalid credentials
login with twitter
deleted log/development.log
Merge branch 'feature/add-twitter-authentication' into develop
added migration and configuration to login with github
errors
test
Merge branch 'feature/login-github' into develop