Docker image for ib-controller

It uses the official base/archlinux and installs the ib-controller AUR package.

It exposes the 4003 port.

To customize the image, use environment variables named like the corresponding options in the configuration .ini file with the IB_ prefix. For example, using docker compose yaml format:

services:
    ib:
        image: ibizaman/docker-ibcontroller
        environment:
            - IB_IbLoginId=username
            - IB_IbPassword=password