display "Recording state in git..." when staging the journal

A bit tricky to avoid printing it twice in a row when there are queued git
commands to run and journal to stage.

Added a generic way to run an action that may output multiple side
messages, with only the first displayed.

Types/Messages.hs

@@ -0,0 +1,20 @@
+{- git-annex Messages data types
+ - 
+ - Copyright 2012 Joey Hess <joey@kitenet.net>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Types.Messages where
+
+data OutputType = NormalOutput | QuietOutput | JSONOutput
+
+data SideActionBlock = NoBlock | StartBlock | InBlock
+
+data MessageState = MessageState
+	{ outputType :: OutputType
+	, sideActionBlock :: SideActionBlock
+	}
+
+defaultMessageState :: MessageState
+defaultMessageState = MessageState NormalOutput NoBlock