Add calls to the callbacks to GameScriptItemInfo::SetName, so that giving a Lua name to an object removes its existing object and any other object currently using the new name, before then putting the name into the map.
Add initial documentation for the Lua-exported parts.
Change pos and rot from arrays to GameScript[Position/Rotation].
Add getters and setters for the members used so far.
Add Init, which for now is needed to get an item working properly.
This is the first pass at wrapping an ITEM_INFO in a struct and handing it over to Lua. Many improvements should follow - this is more of a test implementation.
