This plugin is not a plugin to post on Spigot. This is a plugin you could make for a server. It is a german plugin, so most people won't understand it, and it has nothing to deal with own servers. Once I looked into the code I didn't even install it, as I could rather create it by myself. You should really add configuration parts in here, to make sure it is compatible for all servers!
Btw, the source isn't bad but for the goal it is posted, so people can use it and have benefits of it, it is a just a very bad plugin in its category..