Added Client object, Users.company, Projects.client
started implementing ``create_alembic_table()`` to ``stalker.db`` module
Merge branch 'develop' of https://github.com/Industriromantik/stalker into Industriromantik-develop
updated User and Project classes, tests of them and the new alembic revision related to the new Client class
Merge branch 'Industriromantik-develop' into develop