Nuke qboolean from orbit

I never liked it, but with C2x coming out, it's best to handle bools
properly. I haven't gone through all the uses of int as bool (I'll leave
that for fixing when I encounter them), but this gets QF working with
both c2x (really, gnu2x because of raw strings).

libs/gamecode/pr_parse.c

@@ -212,7 +212,7 @@ ED_NewString (progs_t *pr, const char *string)
 	Can parse either fields or globals
 	returns false if error
 */
-VISIBLE qboolean
+VISIBLE bool
 ED_ParseEpair (progs_t *pr, pr_type_t *base, pr_def_t *key, const char *s)
 {
 	pr_def_t    *def;