Add Byebug to Gemfile
Add Omniauth support to app

* Add omniauth-github gem

* Modify sessions_controller.rb to handle Oauth
  users

* Allow omniauth boolean field to be set via user
  signup pages

* Modify user password requirements for Oauth
  users

* Modified user signup page to hide password
  fields for Oauth users

* Added Omniauth boolean field to Users

* Added Google Oauth support