Update version to 2.3

Increase version to 2.2

Merge pull request #18 from nyfrk/memleak

Fix memory leak

Add image to readme

Add Blt Listener

Add an lua example for calling c functions from lua and vice versa

Add some lua functions

* GetPlayerRace
* GetLocalPlayer
* ShowTextMessage
* AddSettlers
* DeleteWorldCursor
* SetWorldCursor
* SetZoom
* RevealWorldMap

Use the MAKE_INDEX macros to calculate the index

Initial Commit