Tweak monster draining message to be consistent with other messages, and

also to avoid mentioning the attacker's name in case there is no attacker.

git-svn-id: https://crawl-ref.svn.sourceforge.net/svnroot/crawl-ref/trunk@8499 c06c8d41-db1a-0410-9941-cceddc491573

Created by  dolorous  on January 17, 2009
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