Update babel-loader to use the async version of babel.transform

[loganfsmyth]

Like babel/babel#6784, but for babel-loader.

This one probably won't be as difficult since there is less complex surrounding logic.

[michael-ciniawsky]

It's babel.transform(code, options, (err, result) => result) for async usage ?

[danez]

We need to ensure, that we set the peer deps then correct for babel to be >=beta.X where X is the number where it gets released.

[michael-ciniawsky]

There seems to be no async version of babel.transform ? Only babel.transformFile works async. Maybe I'm doing something wrong ¯_(ツ)_/¯

[loganfsmyth]

It's babel.transform(code, options, (err, result) => result) for async usage ?

That is correct. That was added in the PR referenced in the linked issue, so it has not been published yet. When we get a @babel/core@7.0.0-beta.32 it'll be in there.

[loganfsmyth]

This is done!