Safrs

Patch filter count issue (146 )

- Resolved conflicts with recent flask_sqlalchemy.
* `safrs.DB` does no longer exist before `SAFRSAPI` is initialized.

- Improved packaging (fix broken `pip install -e . ` in pip>=22)

- No longer automatically commit instances (`SAFRSBase.db_commit` defaults to `False`)

The flask-sqlalchemy version requirements have been frozen due to an incompatibility with >=3.0.0. A proper fix will be released in the next release but this will require a change in the safrs default "autocommit" functionality (i.e. objects are automatically committed upon initialization in safrs which doesn't always work with flask-sqlalchemy 3).

Fix for 127 (Flask-SQLAlchemy keyref error)

* apply page[limit] also to non-lazy relationships
* default to PK order_by if no `sort=` is specified
* fix missing mssql order_by/sort
* generate apilogicserver schema