Validate delete, disable actions for case status.

We should validate delete, disable actions for case status option group and corresponding values.

1. If we have any case, don't allow to delete and disable actions for case_status option group.
2. Don't allow delete action for all case statuses those are in used.
3. Allow disable for all case statuses. (since which would avoid user to create new case w/ specific status in future )
But make sure to tweak the set default code for existing case if attached to disabled status.
( Here we should load single disabled + all active statuses. )

Also please make sure we should be consistent w/ case_type, encounter_medium and case_status option groups and values.
( since inappropriate disable/delete action for all these group / values lead to break on case activity forms and view pages. )