jetison old warning code

Get rid of most of the vestiges of the old warning code that was
replaced over 7 years ago.  I left the list of colors which were used for
warning flashes.

include/decl.h

@@ -27,9 +27,6 @@ E char SAVEP[];
 E NEARDATA int bases[MAXOCLASSES];
 
 E NEARDATA int multi;
-#if 0
-E NEARDATA int warnlevel;
-#endif
 E NEARDATA int nroom;
 E NEARDATA int nsubroom;
 E NEARDATA int occtime;