Assistant monad, stage 2.5

Converted several threads to run in the monad.

Added a lot of useful combinators for working with the monad.

Now the monad includes the name of the thread.

Some debugging messages are disabled pending converting other threads.

Assistant/WebApp/SideBar.hs

@@ -73,7 +73,7 @@ getSideBarR nid = do
 {- Called by the client to close an alert. -}
 getCloseAlert :: AlertId -> Handler ()
 getCloseAlert i = do
-	dstatus <- getAssistantY daemonStatus
+	dstatus <- getAssistantY daemonStatusHandle
 	liftIO $ removeAlert dstatus i
 
 {- When an alert with a button is clicked on, the button takes us here. -}