More functions to compat.

Moved:
* doPlayerRemoveItem
* getThingPos
* getHouseByPlayerGUID
1) Like this?
```lua
local thing
if uid >= 0x10000000 then
	thing = Creature(uid)
else
	thing = Item(uid)
end
```
2)  What about this function to get the stackpos?
```cpp
int32_t LuaScriptInterface::luaTileGetThingIndex(lua_State* L)
{
	// tile:getThingIndex(thing)
	Tile* tile = getUserdata<Tile>(L, 1);
	if (tile) {
		Thing* thing = getThing(L, 2);
		if (thing) {
			lua_pushnumber(L, tile->__getIndexOfThing(thing));
		} else {
			lua_pushnil(L);
		}
	} else {
		lua_pushnil(L);
	}
	return 1;
}
```