Flask-Oauth is no longer mantained, and the best for PYBOSSA is to
remove it. Also, Twitter, Facebook and Google signin have not been used
as widely as the local account. Thus, removing that unused code is for
the best.
Coverage decreased (-0.4%) to 97.515% when pulling 5d60863748ab4d9f34c3fed07cf3c26807ad8237 on chore-remove-oauth into add4e7b4e5eff99d7a81505fa2a6bc078cb6913d on master.
Flask-Oauth is no longer mantained, and the best for PYBOSSA is to remove it. Also, Twitter, Facebook and Google signin have not been used as widely as the local account. Thus, removing that unused code is for the best.