Fix method ChestInventory.selectItemAtWithShift

[opl-]

Bug: Method ChestInventory.selectItemAtWithShift crashes every time you call it with slot >= 54.

Fix:

@Override
public synchronized void selectItemAtWithShift(int slot) {
    delay();
    ItemStack item = getItemAt(slot);
    int rangeStart, rangeEnd;
    if(item == null)
        return;
    if(slot < items.length) {
        rangeStart = items.length;
        rangeEnd = items.length + inventory.length;
    } else {
        rangeStart = 0;
        rangeEnd = items.length;
    }
    boolean slotFound = false;
    for(int i = rangeStart; i < rangeEnd; i++) {
        if((slot < items.length ? inventory[i - items.length] : items[i]) == null) {
            if(slot < items.length) {
                items[slot] = null;
                inventory[i - items.length] = item;
            } else {
                items[i] = item;
                inventory[slot - items.length] = null;
            }
            slotFound = true;
            break;
        }
    }
    if(!slotFound)
        return;
    bot.getEventBus().fire(new InventoryChangeEvent(this, slot, 0, (short) 0, item, true));
}

I tried making a PR but i failed. My GitHub skills are just terrible, so I'm posting this as an issue with proposed fix.

[DarkStorm652]

The inventory system is rather poorly implemented and now outdated.