Flask-migrate

- Allow to init_app correctly without specifying db. [118](https://github.com/miguelgrinberg/flask-migrate/issues/118) ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/e339f27b8ee3e932d74fff91344b615fe6170333)) (thanks **Victor Akimov**!)

- Allow db to be provided separately from the app ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/d612c10c05ceab7e1131839ab8a7eadcc4a71beb))
- Added missing Python 2 version classifier to package ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/6f321543fec6c04b445c34c312092c45deaf2d29))
- Fix the link for flask-sqlalchemy binds [99](https://github.com/miguelgrinberg/flask-migrate/issues/99) ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/6bf0452b084f14d06e56784465240e0258b710cb)) (thanks **lord63**!)
- Update the way to import the flask extension [98](https://github.com/miguelgrinberg/flask-migrate/issues/98) ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/c27cfea43d923b991b5f609a94a58efcdca4fe3b)) (thanks **lord63**!)

- configuration callbacks ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/835d3e4b33bfbd7dae2166b88c49aee8f5fbeac0))
- Update __init__.py Update description of edit command. ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/3a657dcb683ff3b91cb9e2393fbdaaa11ea33b8a)) (thanks **Kostyantyn Leschenko**!)
- fixed link in documentation ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/738d33cd76185455063d9499f7752b846193889a))

- Add edit command [76](https://github.com/miguelgrinberg/flask-migrate/issues/76) ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/e9c855ca8a935bc55e830481073e377d09cdf66d)) (thanks **Jelte Fennema**!)
- Updates so that directory doesn't get overridden [78](https://github.com/miguelgrinberg/flask-migrate/issues/78) where directory gets overridden if it is not explicitly specified in init_app. This fix allows it to be set when the `Migrate` object is initialized and not automatically get overridden when the `init_app` is called. This is a non-breaking change. ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/0c9a2cbe35953cdabca571f402883c202ddfa09f)) (thanks **Tim Martin**!)

- Do not generate a migration if no schema changes are found ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/626c83feb49f571c2a4468a8fc9f81a44eecc451))
- Fix the merge command by allowing more than one argument. [74](https://github.com/miguelgrinberg/flask-migrate/issues/74) ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/9c62c963c0e142a40233dd6dde17925cdc34ea9d)) (thanks **Kevin Dwyer**!)

- Make the multi-database configuration fully automatic ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/ed1606c02dd3e57580d853db6ebe66804a5f0ceb))
- Add sane default for `db downgrade --sql` [71](https://github.com/miguelgrinberg/flask-migrate/issues/71) ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/01a2e701259e7792c82b2173587750efe5523877)) (thanks **Anthony Miyaguchi**!)
- Add support for multiple databases migration [70](https://github.com/miguelgrinberg/flask-migrate/issues/70) ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/07737da36faf103987a9aa1df1e39ab8259b5181)) (thanks **Nan Jiang**!)
- Added support for -x option ([commit](https://github.com/miguelgrinberg/flask-migrate/commit/a2ff9d668393e4d2da555dc145ee80c065ac932a)) (thanks **jesse**!)