Adding "Delete all App Clones" option on Cloned Apps page.

This option is seen by clicking the '3-dot' menu on Settings->Cloned Apps page and requires:
1. Flag 'remove_all_cloned_apps' to be turned on.
2. Cloned UserId to be present in system.

Test: Manually setting the flag, creating clones.
Change-Id: I83ff40923f7932ed6b23cb831bdcd2cb9252d295