Deuce wants js.exec() to support non-number return values via exit_code

<@Deuce> Just saying that if someone does the work of exit_code = {thing: function(x) { return secretsauce }); exit(); they should get away with it.

src/sbbs3/js_internal.c

@@ -466,7 +466,7 @@ js_execfile(JSContext *cx, uintN argc, jsval *arglist)
 	}
 	else {
 		jsval exit_code = JSVAL_VOID;
-		if(JS_GetProperty(cx, js_scope, "exit_code", &exit_code) && JSVAL_IS_NUMBER(exit_code))
+		if(JS_GetProperty(cx, js_scope, "exit_code", &exit_code) && exit_code != JSVAL_VOID)
 			rval = exit_code;
 	}
 	JS_SET_RVAL(cx, arglist, rval);