Load babel via standalone instead of npm

Basically I would want the same behavior as https://github.com/babel/website/pull/1284 and https://github.com/babel/website/pull/1356 by @Daniel15

This would be amazing (especially once we move preset-env/babylon into the monorepo again). It would allow easy checking of the AST when we make parser changes, and make it easier to test plugin changes as well.

Basically it would allow for a url to be generated that loads the version of Babel from the PR/branch.

Then we wouldn't have to update the version of Babel every time either (depends on what we want the default to be)