Currently [[`git-annex-fsck`|git-annex-fsck]] gives a warning for all my files stored with MD5 keys that they can be upgraded to the more secure SHA256: `Can be upgraded to an improved key format. You can do so by running: git annex migrate`.  In my case the key choice is deliberate, so it would be good if this warning could be disabled, to prevent it from drowning out more serious ones.
