understand adjusted view branch names

An adjusted view branch has a name like
"refs/heads/adjusted/views/master(author=_)(unlocked)", so it is a view
branch that has been converted to an adjusted branch.

Made Logs.View support such branch names. So now git-annex sync and
pre-commit handle updating metadata on commit in such a branch.

Much remains to be done to fully support adjusted view branches,
including actually applying the adjustment when updating the view branch.

Sponsored-by: Graham Spencer on Patreon

Command/PreCommit.hs

@@ -45,10 +45,9 @@ seek ps = do
 	runAnnexHook preCommitAnnexHook
 
 	-- committing changes to a view updates metadata
-	mv <- currentView
-	case mv of
+	currentView >>= \case
 		Nothing -> noop
-		Just v -> withViewChanges
+		Just (v, _madj) -> withViewChanges
 			(addViewMetaData v)
 			(removeViewMetaData v)