Admin can delete a whole participatory process even if it contains elements

This bug report has in turn two bugs reported: 1. From the Backoffice, an Admin can delete a whole participatory process even if it contains elements (like components with Proposals). 2. In this case the Participatory Process and all its Components are deleted, but the Proposals (with comments, votes, etc..) remain in the database orphaned as garbage. The same may probably happen to blog posts, debates, etc.. I expect the admin panel to either block deletion if the space contains data or allow deletion but advise the admin that the space contains data, in this latter case all the data inside the space should be deleted in cascade. The same may happen to Assemblies, initiatives, etc.