More raygui functions and updated to raygui v3.2-dev.

src/core.c

@@ -301,6 +301,18 @@ int lcoreSetWindowTitle( lua_State *L ) {
 	return 1;
 }
 
+/*
+> count = RL_GetMonitorCount()
+
+Get number of connected monitors
+
+- Success return int
+*/
+int lcoreGetMonitorCount( lua_State *L ) {
+	lua_pushinteger( L, GetMonitorCount() );
+	return 1;
+}
+
 /*
 > RL_CloseWindow()