Fixes #4369 - Added link to filters page on RBAC form

Load filters table in roles UI via ajax
Fixes #5139 - leftovers subscribe_to_all_hostgroups

Remove user_xxx unnecessary tables and notices

Update subhostgroups removed

Fixes for migration of foreign keys

Remove users from compute_resource fixture

Remove table notices after fk are removed for pg/mysql
Fixes #3309: Support deep merging of hash and array structures in smart class parameters

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changing continue_looking to merge_overrides, will squash later