multiple -m

sync, assist, import: Allow -m option to be specified multiple times, to
provide additional paragraphs for the commit message.

The option parser didn't allow multiple -m before, so there is no risk of
behavior change breaking something that was for some reason using multiple
-m already.

Pass through to git commands, so that the method used to assemble the
paragrahs is whatever git does. Which might conceivably change in the
future.

Note that git commit-tree has supported -m since git 1.7.7. commitTree
was probably not using it since it predates that version. Since the
configure script prevents building git-annex with git older than 2.1,
there is no risk that it's not supported now.

Sponsored-by: Nicholas Golder-Manning on Patreon

Annex/View.hs

@@ -577,7 +577,7 @@ updateView view madj = do
 			cmode <- annexCommitMode <$> Annex.getGitConfig
 			let msg = "updated " ++ fromRef (branchView view madj)
 			let parent = catMaybes [oldcommit]
-			inRepo (Git.Branch.commitTree cmode msg parent newtree)
+			inRepo (Git.Branch.commitTree cmode [msg] parent newtree)
 		else return Nothing
 
 {- Diff between currently checked out branch and staged changes, and