Bug 2012185 - add validation step to nimbus-fml generate

[moibra05]

Updates nimbus-fml generate to include the same validation logic as nimbus-fml validate allowing build scripts to rely solely on generate

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[freshstrangemusic]

I would like to see a test where we invoke the generate command and it fails for something in validate (ie the test will fail without this patch)

The pull request has been modified, dismissing previous reviews.

The pull request has been modified, dismissing previous reviews.