Allow user to clear all caches somewhere

[1-alex98]

It will happen that bad content ends up int the cache.db or other jsons, engine data or what ever that results in unexpected errors.

First point in tec support guidline would be clear cache. But this is hard finding several hidden folder seems to be a hard task for some users.

Good would be an option in the installer or deinstaller (checkbox delete caches). Alternatively offer a button in the client (can not be used if client can not start up). Such options make tec support 110% easier :D