Merge pull request #100 from greboid/master

Optmise docker file.
Merge pull request #101 from greboid/master

Update run script
Build docker image.
Merge pull request #102 from csmith/master

Build docker image.
Add caching of docker images to CI script.
Merge pull request #103 from csmith/master

Add caching of docker images to CI script.
Switch to ubuntu as base image.