Added SQLAlchemy models for tag alias and implication relations.
Added test scripts to test basic tag functionalities. This does not include implication and alias which will have their own test scripts.
Added art description and corresponding tests. Each art entry can have their own description now and the models and tests have been altered to cover them too.
Renamed several DB tables to fit schema change.
Introduced DBCollection to fit schema change.
Added DBTagCategory.tags.
Changed return values to DB objects instead of single fields
Implemented a way to create, update and delete presences over the API.
Implemented code to list >ALL< artists similar to Art entries. Should be secured against requesting the entire database at some point.
Added debug prints to all API calls for clearer logging