fix savestate.create(integer)

maybe fixes #41 (not sure)

src/lua-engine.cpp

@@ -2711,15 +2711,22 @@ static int savestate_create_aliased(lua_State *L, bool newnumbering) {
 	int which = -1;
 	const char* path = NULL;
 	bool hasArg = false;
-	if (lua_gettop(L) >= 1) {
+
+	if (lua_gettop(L) >= 1)
+	{
 		hasArg = true;
-		path = luaL_checkstring(L, 1);
-		if(path == NULL) {
-			which = luaL_checkinteger(L, 1);
+
+		if(lua_isnumber(L,1))
+		{
+			which = luaL_checkinteger(L,1);
 			if (which < 1 || which > 10) {
 				luaL_error(L, "invalid player's savestate %d", which);
 			}
 		}
+		else 
+		{
+			path = luaL_checkstring(L, 1);
+		}
 	}
 
 	//lets use lua to allocate the memory, since it is effectively a memory pool.