Initial infrastructure changes

[satra]

• strip away girder connections
• switch to github actions for integration
• setup a pytest framework (data + code) to simulate client testing of the api

[yarikoptic]

marked two which I think are done. not sure if switch of CI is really needed. Will leave to @satra to decide if issue is sufficiently handled.

[satra]

let's keep the CI switch aside. just that it is easier for new people to come and see consistency across a project. so you don't need to mental gymnastics to go from one part of the project to another. i'm fine with punting the CI change later, but would be good to converge.