Shiftboiler

A minor release focusing on updating dependencies

A minor release containing some further code cleanups.

This release brings along a few updates:

* Firs of all we are updating to flask 2.0 along with it dependencies (Werkzeug, Click).
* Then we are getting rid of Flask-DebugToolbar feature. You can still install and enable it in your applications manually.
* We are also dropping out-of-the-box support for Flask-Navigation, if you are using it, you will need to manually install and enable it from now on.
* Jinja extensions feature has been merged into boostrap and drops support for Humanize and MomentJs filters.
* Sentry feature is also being removed: the underlying library updates to often for us to track and maintain compatibility. This is better be implemented in userland code.

This is a minor maintenance that finally addresses unpinning outdated version of Werkzeug now we've worked throug updateing our dependencies.

This is a minor maintenance release to update outdated dependencies.

This release contains some refactoring and improvements around bootstrap process.
Specifically it now gracefully handles app module imports and detects when an attempt
has been made to load app from a namespace rather than a regular module and give back
descriptive message with possible resolutions. The app now will bootstrap properly
regardless of whether there's an `__init__.py` file in the root of your application,
which we think should be entirely up to you.

In addition, we changed the environment variables `APP_MODULE` and `APP_CONFIG` to
`FLASK_APP` and `FLASK_CONFG` respectively to act inline with default Flask behavior.
You will need to change these when upgrading an existing app.

This release also includes some other minor changes to code structure and
documentation improvements.