python3 & update packages to latest

[RedCraig]

• Updated test factories to use factory.alchemy.SQLAlchemyModelFactory
• Added orm scoped session for db connections
• Updated packages to latest
• is_authenticated is not callable any more
• updating to python 3 print()
• updating wtforms imports. TextField is now StringField and Required is now DataRequired
• fix for SQLAlchemy error TypeError: unhashable type: 'Role'
• Added @factory.post_generation hook for roles generation when a user is created
• Secret key utf8 encoded to match FlaskTestCaseMixin hmacs version

Updating to latest packages had last been done in #23, which I wish I had checked before updating myself!

[RedCraig]

@mattupstate Wercker fails in the build image step with: 2016/06/09 09:52:38 Could not reach any registry endpoint