Drop close-without-saving confirmation dialog

Anecdotally, most users (including me) rarely want to save their logs,
they just want to record them and read them. In any case, all the
temporary logs are actually kept (forever) in $XDG_CACHE_DIR.

Fixes #15.

Bustle/UI.hs

@@ -433,41 +433,6 @@ showSaveDialog wi savedCb = do
                             \\"%s\".") tempFilePath
                 displayError wi title (Just secondary)
 
--- | Show a confirmation dialog if the log is unsaved. Suitable for use as a
---   'delete-event' handler.
-promptToSave :: MonadIO io
-             => WindowInfo
-             -> io Bool -- ^ True if we showed a prompt; False if we're
-                        --   happy to quit
-promptToSave wi = io $ do
-    mdetails <- readIORef (wiLogDetails wi)
-    case mdetails of
-        Just (RecordedLog tempFilePath) -> do
-            let tempFileName = takeFileName tempFilePath
-                title = printf (__ "Save log '%s' before closing?") tempFileName :: String
-            prompt <- messageDialogNew (Just (wiWindow wi))
-                                       [DialogModal]
-                                       MessageWarning
-                                       ButtonsNone
-                                       title
-            messageDialogSetSecondaryText prompt
-                (__ "If you don't save, this log will be lost forever.")
-            dialogAddButton prompt (__ "Close _Without Saving") ResponseClose
-            dialogAddButton prompt stockCancel ResponseCancel
-            dialogAddButton prompt stockSave ResponseYes
-
-            widgetShowAll prompt
-            prompt `after` response $ \resp -> do
-                let closeUp = widgetDestroy (wiWindow wi)
-                case resp of
-                    ResponseYes -> showSaveDialog wi closeUp
-                    ResponseClose -> closeUp
-                    _ -> return ()
-                widgetDestroy prompt
-
-            return True
-        _ -> return False
-
 maybeQuit :: B ()
 maybeQuit = do
   n <- decWindows
@@ -576,7 +541,6 @@ emptyWindow = do
                               , wiLogDetails = logDetailsRef
                               }
 
-  io $ window `on` deleteEvent $ promptToSave windowInfo
   incWindows
   io $ widgetShow window
   return windowInfo