Cygwin port + "everything" link refactor

The Cygwin port development has lead to a refactoring in `base_package.yaml` and new `copy` functionality for profile links.

See the parallel https://github.com/hashdist/hashdist/pull/156 for enabling functionality in hashdist.

This pull request provides all the packages, patches, and functionality required by a Proteus installation on Cygwin Windows.