Volume Size Overrides

Story: As a Quay administrator I can specify the desired size of storage resources provisioned for managed components so that I can choose a large enough capacity upfront for performance reasons or due to the lack of resize capabilities of the storage backend.

Acceptance criteria:

• volume override options at the Operator API/Custom Resource Level
• volume overrides available for every managed component that uses a PersistentVolume (Postgres for Quay, Postgres for Clair)