[Suggestion] Grue acceptable light level config option(s)

[Laike-Endaril]

Following up on
#13
and
lumien231/Hardcore-Darkness#38

One possible solution is to have a config option for the light level(s) at which a grue can spawn. Ofc I'd still love to see HC Darkness change the server-side light levels, but having configurable grue light levels would be handy in and of itself.

With one number (maximum spawn light level), it allows a workaround for grues not spawning with the grue + HC Darkness combo. This is the only one I really care about tbh.

If you add a second number (minimum spawn light level), it allows a large range of freedom (and makes the daylight grue option obsolete).

If you wanted to really go out of your way, you could also make these numbers per-dimension using a String array config input and split(), trim(), Integer.parse() and all that garbage but on a personal level I really just care about the basic maximum :P