Waypoint and multiworld related bugfixes

[iczero]

• Fix the NullPointerException that occurs due to events firing before the map is initialized
• Expose the show_range waypoint option in the "Edit Waypoints" window
  • TODO: not quite sure how to add localization to this properly
• Allow a solitary negative sign to be present in the waypoint coordinate boxes to allow typing and editing negative numbers directly
• Automatically focus the text box in the world name dialog
• Prevent Enter from opening the chat in the world name dialog
• Load world names in multiworld mixed mode so they do not need to be re-entered after restarting the game
• Prevent multiworld mixed mode world names from leaking to other servers
• Don't sometimes clobber recorded world spawn positions when changing worlds
• Use both world spawn position and dimension id in multiworld mixed mode
• When name is specified in WorldKey, match against name only instead of both name and spawn position
• If a world name is set in WorldKey, don't serialize world spawn position
• Rename WorldManager.registeredWorlds to WorldManager.worldAssociations to prevent confusion with related WorldManager.registeredWorlds() method
• Save WorldManager.worldAssociations instead of WorldManager.worldsData to worlds.json

Edit: multiworld detection still seems to be having issues Edit 2: fixed it, I think

[iczero]

Other things needed:

• [ ] Changing spawn position (~by sleeping in a bed or something~ with /setworldspawn) should preserve waypoints
  • Should work in mixed mode if user provides same dimension name
• [x] Use both dimension spawn position and dimension id in multiworld mixed mode
• [ ] Allow renaming worlds

[Bulldog83]

Ou. I need some time to check it. For localization I've made LangUtil. But it seem like it need some improvements to use it more easily.