Automatically delete / remove TAGS that aren't in use Merged

Summary: Please auto delete tags that aren't actively used.

Sometimes a Tag is created by a user, then later they update the tag with a different name. It seems that Aha 'remembers' the original entry. This is creating large amounts of tags that is unwieldy to manage for admins. It becomes tedious for Admins to manage this list.  In the small screen grab attached, I show at least 5 Tags that aren't being used... :(