Consolidate the player and monster draining functions in fight.cc, make

monster draining take multiple levels of negative energy resistance into account, and only set the necromancy conduct if draining actually took place, as with draining beams.

git-svn-id: https://crawl-ref.svn.sourceforge.net/svnroot/crawl-ref/trunk@8551 c06c8d41-db1a-0410-9941-cceddc491573

Created by  dolorous  on January 18, 2009
WBNFHKUIC3JAIE5ZN6FZ5WIKBGET4U2JJGUDLDZNYQRLQLUYQYGQC
Change contents