Remove damienc from CREDITS.
Remove damienc from CREDITS.

There are no contributions in the tree from this contributor; he only
submitted some "powerglove" fist sprites to the project a long time
ago which were replaced, and subsequently appear to have been stolen
from another project without permission. See comments on this file
on Doomworld:

http://www.doomworld.com/idgames/index.php?file=combos/leftover.zip

CWolfRU/freedoom,jmtd/freedoom,CWolfRU/freedoom,jmtd/freedoom,jmtd/freedoom