fix display of semitrusted repos in status

semitrusted uuids rarely are listed in trust.log, so a special case
is needed to get a list of them. Take the difference of all known uuids
with non-semitrusted uuids.

Logs/UUID.hs

@@ -16,7 +16,8 @@
 module Logs.UUID (
 	describeUUID,
 	recordUUID,
-	uuidMap
+	uuidMap,
+	uuidList
 ) where
 
 import qualified Data.Map as M
@@ -87,3 +88,6 @@ uuidMap = do
 	return $ M.insertWith' preferold u "" m
 	where
 		preferold = flip const
+
+uuidList :: Annex [UUID]
+uuidList = M.keys <$> uuidMap