Libres

- Fixes another incorrect type annotation in `Scheduler`.

- Fixes some incorrect type annotations in `Scheduler`.

- Drops support for Python 3.7 and adds support for 3.11

- Switches to ``pyproject.toml``

- Adds type annotations

- Changes ``Scheduler.allocate`` to avoid hundreds of separate
SQL queries when passing in hundreds of datetime ranges in
order to identify existing overlapping allocations.

Performance could still be a concern, since the query contains
a lot of datetime comparisons. It might be quicker in the common case to filter to the minimum and maximum dates that
have been passed in and doing the overlap checks entirely in
Python. We will need to keep an eye on this.

- Adds additional parameters to ``Scheduler.remove_unused allocations`` to filter the to be removed Allocations by weekday or whether or not they belong to a group.
- Fixes bug in ``Scheduler.search_allocations``. It did not align the days parameter properly to the timezone of the Allocation/Scheduler.
- Pins SQLAlchemy to versions before 2.0

- Drops Python 3.6 support.

- Normalizes availability partitions on 23/25 hours to a 24 hour day so that DST transition days can be rendered the same as regular days.

This can optionally be avoided by passing ``normalize_dst=False`` to the function.

- Adds ``Allocation.normalized_availability`` that reports the availability in the same normalized way.

- Adds extra parameters to ``Allocation.limit_timespan`` that match the new parameters added to ``sedate.get_date_range``.