Added required content configuration.

This includes checking when dropping files that any required content
configuration is satisfied. However, it does not yet include an active
check on the required content; the location log is trusted when checking
the required content expression.

Assistant/Threads/ConfigMonitor.hs

@@ -62,16 +62,17 @@ configFilesActions =
 	, (groupLog, void $ liftAnnex groupMapLoad)
 	, (numcopiesLog, void $ liftAnnex globalNumCopiesLoad)
 	, (scheduleLog, void updateScheduleLog)
-	-- Preferred content settings depend on most of the other configs,
-	-- so will be reloaded whenever any configs change.
+	-- Preferred and required content settings depend on most of the
+	-- other configs, so will be reloaded whenever any configs change.
 	, (preferredContentLog, noop)
+	, (requiredContentLog, noop)
 	, (groupPreferredContentLog, noop)
 	]
 
 reloadConfigs :: Configs -> Assistant ()
 reloadConfigs changedconfigs = do
 	sequence_ as
-	void $ liftAnnex preferredContentMapLoad
+	void $ liftAnnex preferredRequiredMapsLoad
 	{- Changes to the remote log, or the trust log, can affect the
 	 - syncRemotes list. Changes to the uuid log may affect its
 	 - display so are also included. -}