Do not shadow recipe attribute.
Do not delete destdir if keep_destdir config option is set.
Make sure to keep the destdir for child recipes.
Set child recipe destdir to omnibus_dir/embedded.
Use destdir instead of hardcoding /opt/omnibustest/embedded.
Use dispense to be able to use build/install in omnibus recipe.
Remove config attribute from omnibus packager.
Add omnibus-style recipe for fpm-cookery.

This creates a package for fpm-cookery including ruby.
Strip ruby binary and libs.

Reduces package size from 20M to 5M.