sync --quiet

* sync: When --quiet is used, run git commit, push, and pull without
  their ususual output.
* merge: When --quiet is used, run git merge without its usual output.

This might also make --quiet work better for some other commands
that make commits, like git-annex adjust.

Sponsored-by: Kevin Mueller on Patreon

Command/PostReceive.hs

@@ -52,4 +52,5 @@ updateInsteadEmulation :: CommandStart
 updateInsteadEmulation = do
 	prepMerge
 	let o = def { notOnlyAnnexOption = True }
-	mergeLocal mergeConfig o =<< getCurrentBranch
+	mc <- mergeConfig
+	mergeLocal mc o =<< getCurrentBranch