CI builds should always use the `--frozen-lockfile` option. It will fail the build if the lockfile is out-of-date:
> If you need reproducible dependencies, which is usually the case with the continuous integration systems, you should pass --frozen-lockfile flag.
(https://yarnpkg.com/en/docs/cli/install/)
* makes closure compiler threaded
* Dans PR with a closure compiler java version
* Remove unused dep
* Pin GCC
* Prettier
* Nit rename
* Fix error handling
* Name plugins consistently
* Fix lint
* Maybe this works?
* or this
* AppVeyor
* Fix lint
Kayla Ngan