Add a registry for Marketplace packages

For instance, install DM, then DAM, then uninstall DM, DAM must still work. But when DAM was installed, it did not install the stuff it needs which was already install by DM.
So, at least Copy and Delete commands must register and check their target usage in a registry.

It may be required to also manage versions in that registry.

Also, check how it works with hotfixes.