column util was missing from the Docker image, added it and organised the requirements file so it's more human friendly
rearranged the USER argument in the Dockerfile to avoid the scenario where you didnt specify the user and so lose the layers where apt installed all the packages
add the python deps at the end to ensure docker can reuse cached layers if a python dep changes.
update maspsx (I wanted to test latest maspsx against sotn, so this is what led to the other changes!)
columnutil was missing from the Docker image, added it and organised the requirements file so it's more human friendly