Custom Lights

THIS IS ONLY FOR PAPER-SPIGOT SERVERS

## New

- **`/lpl luminosity <targets> <id> <0-10>`**: how hot the middle of a light burns. It holds a white core that grows
  with the value and eases back to the light's own colour further out.
- **`/lpl pivot <targets> <id> <x> <y> <z>`**: the point a light's stretch grows from, on its own axes. Put it at the
  bottom of a beam and the beam only grows upwards.
- **13 new shapes** in `set`, `follow` and `model_id`: `fire` `portal` `lightning` `aurora` `ripple` `plasma`
  `tornado` `singularity` `rune` `flare` `mist` `comet` `laser_door`. They move on their own on the client and bring
  their own look, so a single command is enough.
- **NeoForge clients** are supported, on every version the mod covers. Fabric, NeoForge and Forge players can share the
  same server and see the same lights.

## Changed

- `paste` carries `pivot` and `luminosity`, so a light copied from the editor arrives exactly as it was.
- Replacing a light with `set`, `follow` or `model_id` keeps its animations, its stretch and now its pivot too.
- Tab completion covers the new shapes and the new subcommands, with sensible values suggested for each one.
- The new shapes get the right default direction (the portal stands up, the rest lie the way you would expect).

## Notes

- Players without the mod are unaffected, as always: the plugin only talks to clients that have it.
- The permission is still `customlights.admin` (default: OP).