Fixed lock up during analysing

This update fixes a deadlock when analysing certain beatmaps.
The application is now a bit smaller after rewriting the analysing logic.

Added a feature for synchronising your current export to the folder. If you frequently use this application to update your song library. This would be very useful to remove any song you don't like from osu. It will remove all files that do not belong in the osu library. Please be careful.

As usual, use Java 10 or below.