Reduce spellcasting training to NetHack levels

Spellcasting now requires 20/80/180 training points to advance to
basic/skilled/expert instead of 100/200/400 as in UnNetHack.

UnNetHack 5 also makes training spellcasting easier relative to weapon
and combat skills, but it instead doubles the training points given per
cast, and quadruples it at basic skill, leading to odd meta-gaming where
you'd want to stay at basic skill to speed advancement to future levels.
Fix waking monsters level-wide when entering certain special rooms

This fixes monsters across the entire level having a chance to be woken
when entering certain special rooms for the first time (courts, swamps,
morgues, zoos and nypmh gardens).  This commit amends that by
restricting the effect to monsters in the room being entered.