Minor tweaks and refactors. A half-baked collection support and several UI tweaks.
Just committing these are they are "old" changes and the current state turns out to be pretty stable.
Added the first draft of the browser window and implemented switching between it and the importer window via menu action.
Also renamed window.py to importer_window and abstracted some features into a superclass from which the browser window can also inherit. This allows an equal interface for them.
Also fixed a bug in the db_adapter.py where an old column name was used for a query.
Added a QTextEdit for art descriptions.
Also added the ability to save and load them from the database. Changing of the description field also triggers a unsaved changes prompt.
Fixed a bug where editing the alias or implication of a tag caused a crash.
Also changed titles that were left unedited from the file name to stay empty inside the database and not be filled with the filename