Improve rebuild bundle cache button UI.
Improve rebuild bundle cache button UI.

damiensawyer/cassette,honestegg/cassette,honestegg/cassette,andrewdavey/cassette,damiensawyer/cassette,andrewdavey/cassette,BluewireTechnologies/cassette,honestegg/cassette,andrewdavey/cassette,damiensawyer/cassette,BluewireTechnologies/cassette