Update ArPow tarball build to work with internal repos

[dseefeld]

Clone for ArPow needs to be updated to be able to work with internal repos. This includes:

• Cloning internal repos when building a tarball
• Creating a method of capturing smoke-test-prereqs (since we have no production build)
• Building a tarball with internal feeds

In release/5.0, there are nuget.config files for smoke-tests that are different for internal production build vs. tarball build with smoke-test-prereqs. This needs to be reconciled also. See #2159

[MichaelSimons]

Closing as there is no known work. 6.0 RC2 was an internal release.