Changes

Summary

1. add an API to register custom variables on bukkit side; see #47 (commit: 9d716dc) (details)

Commit 9d716dc305dc0701f7664685bb336ac256db1597 by Flo.e3 add an API to register custom variables on bukkit side; see #47 (commit: 9d716dc)
	api-bukkit/src/main/java/codecrafter47/bungeetablistplus/api/bukkit/BungeeTabListPlusBukkitAPI.java
	common/src/main/java/codecrafter47/bungeetablistplus/common/BTLPDataKeys.java
	bukkit/src/main/java/codecrafter47/bungeetablistplus/bukkitbridge/BukkitBridge.java (diff)
	common/src/main/java/codecrafter47/bungeetablistplus/common/PlaceholderAPIDataKey.java
	pom.xml (diff)
	bukkit/pom.xml (diff)
	bungee/src/main/java/codecrafter47/bungeetablistplus/bridge/BukkitBridge.java (diff)
	api-bukkit/pom.xml
	bukkit/src/main/java/codecrafter47/bungeetablistplus/bukkitbridge/placeholderapi/PlaceholderAPIDataAccessor.java (diff)
	bungee/src/main/java/codecrafter47/bungeetablistplus/bridge/PlaceholderAPIHook.java (diff)
	api-bukkit/src/main/java/codecrafter47/bungeetablistplus/api/bukkit/Variable.java