Remove deprecated Mining package

[pmbittner]

The org.variantsync.diffdetective.mining package is from the early days of DiffDetective and not in use anymore, and will likely never be. Currently, it is more of a distraction and maintenance burden. Hence, it should be deleted. Some class might still be in use though or generally useful (e.g., the formats). These class should be moved to proper other packages. There are also some scripts and in the scripts directory as well as a python code base in the mining directory, both of which are not in use anymore and work together with the deprecated org.variantsync.diffdetective.mining package. So these could be deleted too. In any case, everything we delete here still survives in the git history in case we need it ever again.