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

Annex/AdjustedBranch.hs

@@ -362,9 +362,9 @@ adjustToCrippledFileSystem = do
 commitForAdjustedBranch :: [CommandParam] -> Annex ()
 commitForAdjustedBranch ps = do
 	cmode <- annexCommitMode <$> Annex.getGitConfig
-	void $ inRepo $ Git.Branch.commitCommand cmode $
-		[ Param "--quiet"
-		, Param "--allow-empty"
+	let cquiet = Git.Branch.CommitQuiet True
+	void $ inRepo $ Git.Branch.commitCommand cmode cquiet $
+		[ Param "--allow-empty"
 		, Param "-m"
 		, Param "commit before entering adjusted branch"
 		] ++ ps