Fix syntax errors in easyNPCs
fix dog alchemy quest entry point
make search for a random free field more fail safe on the edge of the map

also get rid of a while true loop
localize variables and fix style
make search for a random free field more fail safe on the edge of the map
get rid of an unneeded declaration
style fixes, no functional change
reduce movepoints of newly spawned spiders, adjust wear level of a poison cloud
add the skull riddle to Akaltut's dungeon
use a common function to find a free tile to spawn monster.

fix #10370
Merge branch 'develop' of https://github.com/Illarion-eV/Illarion-Content into develop

Conflicts:
	item/id_519_tombstone.lua
	item/skull.lua