Reimplement storyshots integration to allow for local testing
Currently it is not possible to run visual regression tests locally (or update them locally) because the generated screenshots render differently from thew way they do in our CI job. This is due to a difference in operating system and browser versions (different core OS elements, different font-rendering, etc).
I propose that we encapsulate our puppeteer/browser/os scripting for storyshots into a docker image that can be run both locally and in CI to produce deterministic visual regression snapshots regardless of ones working environment.