CORE-4600 Refactor deleteDiskResources for cached results.

Refactored DiskResourceServiceFacadeImpl#deleteDiskResources to use DiskResourceUtil#asStringIdList.
Refactored deleteDiskResources to remove any cached folders found in the success response of the delete service call.
CORE-4600 Refactor DiskResourceServiceFacadeImpl for refresh events.

Moved the DiskResourceRefreshEvent from the ui-disk-resource-module, and removed the obsolete 'tag' parameter.
Refactored DiskResourceServiceFacadeImpl to implement and register itself as a DiskResourceRefreshEventHandler in order to remove the cached child folders of any refreshed parent folder.