Deprecate holding_tail

The bulk update request #13728 has been approved by @evazion.

deprecate holding_tail

Ambigous tag, even the wiki tells people to use either holding own tail or holding another's tail (and it's missing holding with tail).

The bulk update request #13739 has been approved by @evazion.

mass update holding_tail (holding_own_tail or holding_another's_tail) -> -holding_tail

There's also tail grab and grabbing own tail btw.

The bulk update request #13739 (forum #227894) has been approved by @evazion.

The bulk update request #13728 (forum #227855) has been approved by @evazion.