Central Pagination System, take 2.

[Andre601]

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Description

This PR implements a central PaginationHandler class which as the name suggests will be used to handle the pagination of the various menus in a more general way.

I wasn't too happy with my previous attempt (#29) so I decided to redo it. The main difference is, that this system is now in a completely separate package called pw.chew.jdachewtils.menu. This was the easiest way for me to not have major breaking changes that could frustrate the end user when updating.

I also made a central Builder interface instead of an abstract class... Not to sure about that one tbh, but it feels cleaner than the abstract stuff.

To-Do

• Copy all menus over that can be supported by the PaginationHandler.
  • ButtonMenu Cannot be supported due to it allowing multiple buttons/reactions
  • EmbedPaginator
  • OrderedMenu Not doable due to its more complex handling of things
  • Paginator
  • SelectionDialog Seems a bit too complicated for the simple PaginationHandler to.. handle
  • Slideshow