
The list of image formats has become customisable, but didn't have a default which can cause issues since it's a required field when creating a new image. Also document the setting. Additionally, mark OpenStack settings documentation as "(Partial)" until #1221115 is closed. Change-Id: I980c2d61bc9f9ac14fa39e5088c2ce03c48499b2 Closes-Bug: #1223427