Hope to add a world whitelist feature

[NeglectDream]

Plugin Version:

3.6.13

Request:

When using multi-world or per-world plugins, worlds are often hot-loaded and hot-unloaded, but BetterRTP still loads the config for every world that appears.
Please add a World Whitelist so the plugin only enables itself on the worlds listed, saving resources.

How/Why:

Constantly creating and caching configs for worlds that are loaded on-the-fly causes unnecessary performance overhead.

Additional Context:

There is already a DisabledWorlds list in the config—adding a WhitelistedWorlds option below it would be ideal.