Also reduce client packets by tracking dynalight node
ttl in-memory instead of meta. Lights might flicker out
a bit on area first loading, but some startup judder is
expected on any unloaded area anyway.
Add a "cheat" code for torch testing, and possibly for
other dev uses.
Use the upstream coal textures from the fire mod, since that's
already a dependency, and we can make sure our textures are
consistent with the upstream ones. Make the burning torch tip
look embery and not just coaly.
