added git-annex remotedaemon

So far, handling connecting to git-annex-shell notifychanges, and
pulling immediately when a change is pushed to a remote.

A little bit buggy (crashes after the first pull), but it already works!

This commit was sponsored by Mark Sheppard.

RemoteDaemon/Transport/Ssh/Types.hs

@@ -0,0 +1,32 @@
+{- git-remote-daemon, git-annex-shell notifychanges protocol types
+ -
+ - Copyright 2014 Joey Hess <joey@kitenet.net>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE TypeSynonymInstances, FlexibleInstances #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+
+module RemoteDaemon.Transport.Ssh.Types (
+	Notification(..),
+	Proto.serialize,
+	Proto.deserialize,
+	Proto.formatMessage,
+) where
+
+import qualified Utility.SimpleProtocol as Proto
+import RemoteDaemon.Types (RefList)
+
+data Notification
+	= READY
+	| CHANGED RefList
+
+instance Proto.Sendable Notification where
+	formatMessage READY = ["READY"]
+	formatMessage (CHANGED shas) = ["CHANGED", Proto.serialize shas]
+
+instance Proto.Receivable Notification where
+	parseCommand "READY" = Proto.parse0 READY
+	parseCommand "CHANGED" = Proto.parse1 CHANGED
+	parseCommand _ = Proto.parseFail