be quiet when reading cluster and proxy information at startup

I had a transfer of 3 files fail like this:

git-annex: transferrer protocol error: "(recording state in git...)"

The remote had stalldetection enabled, although I didn't see it stall.
So git-annex transferrer would have been started up. I guess that
one of these new git-annex branch reads, that happens early, caused
that message due to perhaps an uncommitted git-annex branch change.

Since the transferrer speaks a protocol over stdout, it needs to be
prevented from outputting other messages to stdout. Interestingly,
startupAnnex is run after prepRunCommand, so if a command requests quiet
output it would already be quiet. But the transferrer does not, instead
it calls Annex.setOutput SerializedOutput in its start action.

Annex/Startup.hs

@@ -34,7 +34,7 @@ startup = do
  - Alternatively, run after initialization.
  -}
 startupAnnex :: Annex ()
-startupAnnex =
+startupAnnex = doQuietAction $
 	-- Logs.Location needs clusters to be loaded before it is used,
 	-- in order for a cluster to be treated as the location of keys
 	-- that are located in any of its nodes.

Remote/Git.hs

@@ -94,7 +94,7 @@ list autoinit = do
 	c <- fromRepo Git.config
 	rs <- mapM (tweakurl c) =<< Annex.getGitRemotes
 	rs' <- mapM (configRead autoinit) (filter (not . isGitRemoteAnnex) rs)
-	proxies <- getProxies
+	proxies <- doQuietAction getProxies
 	if proxies == mempty
 		then return rs'
 		else do