integrate Storybook for further frontend development (mozilla-rally#98)

* set up

* updated README for storybook

* applied requested changes

* fixed conflicts

* Cloud functions and rules (mozilla-rally#101)

* flatten out and run one browser and config per overall run, and be more aggressive about re-trying obscured elements

* run one combo of browser+extension+headlss per-test-run

* add readme explaining screenshots dir

* leave Chrome non-headless commented out, but fix command to make it easier to enable later

* move the extension log scraping to a utility function

* start figuring out how to load studies into firestore

* use trigger function to create user documents

* study add admin script, might move this to a cloud function

* add rules so we can tests in emulator and deploy from here

* add rules with explanations for why they are needed, and make the auth trigger create all the needed documents

* switch to pulling studies from studies subcollection instead of enrolledStudies map, and update test extension to latest rally-sdk which does this as well

* switch svelte app to use user studies subcollection

* add watch target which runs emulators

* add the studyId as a custom token, so we can check using firestore rules

* user studies are now individual documents in firestore

* no longer need to import canned data, set it up at the begining of the test instead

* load data before running tests

* load data before running tests

* create user for test runs

* comment

* email user must sign in after verification to get new token with email_verified claim

* wait for emulated google auth window to appear

* remove debug

* start the UI in watch mode

* enable source maps, so debugging selenium tests is easy

* add missing await, and search for the proper log messages

* remove rally-sdk from main package.json, only need it when updating the test extension

* keep studies list as typescript for now

* fix entrypoint for functions

* fix main entry point for functions

* temporarily disable, debugging slow animations

* more reliable way to wait for slow elements

* run svelte in dev mode for run watch

* load static studies list more reliably in watch mode

* do not run prebuild

* upgrade to latest rally-sdk, no longer fires the useless first pause state change callback

* remove rally sdk

* remove redundant command

* remove firefox nightly support, just use release

* rename test to something more appropriate

* remove unused imports

* more verbose logging if element is not found or clickable

* import readline

* update test extension to latest rally-sdk

* remove rally from main package.json for circle

* see if disabling notifications helps with intermittent test failures

* await action, and load firefox extensions temporarily due to release firefox

* only load firefox extensions when flag is passed

* move rally ID generation to cloud function

* use npm run dev vs. watch, for consistency

* do not create userStudy docs from backend, the site should do this

* change flag to emulator mode vs. test-integration mode

* squelch preventAssignment message

* make dev command output more self-explanatory, and also detail in README

* remove unused dependency, and make build target build functions too

* fix bad merge

* iterate over studies list vs. hardcoded exampleStudy1, also prefer emulator-mode to integration-mode

* use studyId vs addonId

* put studyId as a value in the doc for expedience

* use userStudies and studyID consistently, and watch whole collection not individual docs

* remove debugging

* use studyId not studyID

* set studyId inside

* pause before loading data

* listen for changes after signup too, which resolves broken test

* only check extension logs on firefox until we get cross-browser study cards

* Remove debugging

* got latest

* got latest

* setting up

* resolved conflicts

* returned tgconfig to original

Co-authored-by: Robert Helmer <rhelmer@mozilla.com>