Changelog:

• Better support for 1.13.1+
• Fixed PlaceholderAPI placeholders
• Bukkit plugin now lets BungeeCord know that the server is shutting down
• No more errors if the player leaves the server when the message is sending

Some code structure stuff:
To support more than one NMS version, there's a need to use several server jars. Thanks to the Maven, that can't do it without some thicks, a huge file reorganization has been done. In compiled file - everything is the same, but the source code is now harder to edit.
Thankfully, 3 days ago there was commit that allowed an easier way for sending server brand messages. Expect some kind of rewrite for 1.14.

Also, I want to make a mod-companion for this plugin. There will be an update which describes all new features that will be added with a mod.