* build: unify YARN_VERSION variable usage and ensure CI uses yarn not npm
* chore: use a JS helper so that it can work on windows
* chore: make script/yarn without node_modules installed
* Removes un-used and non-functional code coverage helpers
* Removes un-used release script aliases
* Moves TLS to a lib folder for cleaner directory structure
* Implements start.py as start.js for the GN build
* Adds a re-usable getElectronExec helper for future scripts
* Refactors spec runner to use the helper
