Jsonlitedb

- Accept pathlib.Path objects or existing database connections. The latter enabled additional flexibility to backup and make copies
- Adds about() method
- Cleaned up repo

- Added a `purge()` method, which is just `remove()` without any queries.
- Made empty queries be handled as everything (i.e., `WHERE 1 = 1`) to better match direct SQL queries without a "WHERE" clause.
- Enables updating all rows with `patch()` and no query.
- *Internal*:
- Combined and renamed two private methods that are always called together.
- Cleaned up docstrings.

- WAL mode is now optional but on by default. Adds a wal_checkpoint() method and and calls it by default on close.

- Adds `patch()` based on SQLite's `JSON_PATCH` ([docs](https://www.sqlite.org/json1.html#jpatch)) to update entries quickly and efficiently without loading into Python.
- Improved documentation internally including more docstrings (and more consistent)
- Fixed missing CLI entry-point in `setup.py`

Mostly documentation. Also fixed and clarified using queries on non-dict items.