ZKL: skirmisher now able to read *.sdd mods folder

This will allow us to put ZK repository in "datadir/games" as *.sdd folder and use ZKL Skirmisher to launch the game. ZKL will have GUI to manage AI, startpos, options and engine version.

Also, I learn something new while making Skirmisher read LUA file, maybe will create a replay filter (like a local version of website replay browser)