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.

src/decl.c

@@ -20,9 +20,6 @@ char *catmore = 0;		/* default pager */
 NEARDATA int bases[MAXOCLASSES] = DUMMY;
 
 NEARDATA int multi = 0;
-#if 0
-NEARDATA int warnlevel = 0;		/* used by movemon and dochugw */
-#endif
 NEARDATA int nroom = 0;
 NEARDATA int nsubroom = 0;
 NEARDATA int occtime = 0;