make DropDead transition minimize remote.log for dead sameas remotes

All that needs to be retained in remote.log is the sameas-uuid.
The rest of the config is eliminated. This doesn't save enough space to
bother with, but it prevents anything sensitive in the config of the
dead sameas remote from lingering around.

Note that minimizesameasdead does not update the VectorClock when
changing the log line. That's normally a no-no, but in this case,
it makes each DropDead result in the exact same file contents,
and vector clocks are not needed because the transition breaks
the history chain.

Logs/Remote.hs

@@ -26,16 +26,15 @@ import Logs.Remote.Pure
 import Annex.SpecialRemote.Config
 
 import qualified Data.Map as M
-import Data.ByteString.Builder
 
 {- Adds or updates a remote's config in the log. -}
 configSet :: UUID -> RemoteConfig -> Annex ()
 configSet u cfg = do
 	c <- liftIO currentVectorClock
 	Annex.Branch.change remoteLog $
-		buildLogOld (byteString . encodeBS . showConfig)
+		buildRemoteConfigLog
 			. changeLog c u (removeSameasInherited cfg)
-			. parseLogOld remoteConfigParser
+			. parseRemoteConfigLog
 
 {- Map of remotes by uuid containing key/value config maps. -}
 readRemoteLog :: Annex (M.Map UUID RemoteConfig)