because we missed the major release, this could be a breaking change for anyone using it already with custom shims. We need to remove the directories.lib override to ensure it is non-breaking.
Allows to import language components ahead of time, to include them in bundles:
```
import ace from 'ace';
import 'ace/mode-javascript.js';
import 'ace/theme-twilight.js';
```
It doesn’t solves the issue with workers components however.
Damien Lebrun