Add support for the angular CLI

[mattlewis92]

Use the convertNxGenerator helper from nx devkit to do this: https://nx.dev/nx-api/devkit/documents/convertNxGenerator

Also requires setting a builders entry in the package.json

[MPalix86]

any news ?

[mattlewis92]

This isn't something that I have the time to work on myself, but will happily review and accept a PR to add it!