Set the default level to 4.

It was supposed to be 2, but for some reason I neglected to set it when I
set up the options parsing. However, level 4 is the standard for production
maps, and it happens to be faster than level 2 (at least for gmsp3v2.bsp)

tools/qfvis/source/options.c

@@ -94,6 +94,7 @@ DecodeArgs (int argc, char **argv)
 	options.verbosity = 0;
 	options.bspfile = NULL;
 	options.threads = 1;
+	options.level = 4;
 
 	while ((c = getopt_long (argc, argv, short_options, long_options, 0))
 		   != EOF) {