Enable CSRF protection

- CSRF is enabled by default for login form
- This commit resolves issue #34

Update README.rst to include bower install step

Fixes https://github.com/sloria/cookiecutter-flask/issues/62

Init the flask-migrate extension first

fix db fixture for model tests

Add psycopg2 to production requirements

Add a lint command with flake8 and isort

Update requirements, pin modules to the latest version, …

Add `urls` and `clean` commands to manage.py

Two new useful commands for manage.py. `m urls` lists all URLs (like `rake routes` in Rails). `m clean` gets rid of .pyc files.

Update extension imports to flask_*

See mitsuhiko/flask#1135

Only ignoring the env directory to avoid conflicts with alembic's env.py

Fix typo in generated README.rst

Fix ScopeMismatch error when testing

- Add the UTF-8 marker to files without it.
- Fix some hanging indents.
- Change ''' into """ in docstrings.
- Enforce two blank line rule.

The `testapp` fixture depends on the `app` fixture, but the `app` fixture's
scope was redefined as 'function' in commit 35c32e, which is narrower than
the scope of `testapp` ('session').

Since `testapp` only depends only on `app`, it is safe to make it's scope match
`app`.

Bump year