Log Message:
py-sqlalchemy-migrate: updated to 0.12.0

0.12.0
* Change title in README.rst
* Don't use deprecated / non-functional "force" parameter
* Use legacy\_alter\_table ON in sqlite recreate\_table
* Remove py26 support
* Add .eggs in .gitignore
* Import MutableMapping from the correct Python module
* Update mailinglist from dev to discuss
* Get rid of psycopg2 warnings by disabling wheels
* Enforce that pbr used is >= 1.8