Added option for remembering state of mention all and long tweet

src/app-configuration.defaults

@@ -17,6 +17,9 @@ log_level = string(default="error")
 load_keymap = string(default="default.keymap")
 donation_dialog_displayed = boolean(default=False)
 check_for_updates = boolean(default=True)
+remember_mention_and_longtweet = boolean(default=False)
+longtweet = boolean(default=false)
+mention_all = boolean(default=False)
 
 [proxy]
 type = string(default="Direct connection")