write a conda environment.yml to the python_runtime/ folder so that we can more easily audit what's included in our runtime between builds

migrate the pip dependencies from package.sh to our conda environment file. this will include them in our buildbucket & keeps our package script leaner.

adds a .gitlab-ci.yml which builds the package and uploads artifacts. we also now use the master branch from glmtools.

Requires djhoese github branch for glmtools to work without matplotlib