New Gehenna end.

New Gehenna end.

Standard re-interpretation of trends in hell end structures paired with
diagonal mirroring symmetry and diversionary layout tactics, plus
finnicky and thorough minor pillar randomization and excess monster
definition for tangential spawns, with a focus on open-space diagonally
oriented level traversing and the vague notion of the non-orthodox
non-creator-set end. Same old style as dis_hangedman and coc_hangedman,
in other words, except mucking with the most solidly-designed of the hells
(said status due to the sheer effectiveness in design of hellfire and
fire monsters compared to the other hells, other elements, etc.)

To address: The player can get quite close to endless lava in this end,
which makes the previous minor issue of endless lava having the same
console glyph / colour / tiles tiles much more noticeable. They should
get different graphics, in the same fashion as open sea spaces.