Cleanup /opt/rhodecode/store

Please note that use of sqlite here is important, and shouldn’t be changed despite using other type of Database.

During a new installation if user would point to an existing database it would be re-created destroying of old data. If we use always sqlite the trick here is that new DB will be created on sqlite database file, not touching existing database. The installation step is only for creating the binaries again since nix store was cleaned.

Hope this is clear now