Configure PyPI releases

Configure PyPI releases

This changes adds the following functionality for PyPI releases

- macros
 - A PyPI server macro

- scripts
 - A script to build artifacts
 - A script to publish artifacts

- templates
 - Templates for release

- jobs
 - Jobs for release
   - Nexus3 staging
   - Nexus3 release
   - PyPI index will be added at a later date

Issue-ID: CIMAN-137
Change-Id: I53522ed2fa2f462afebaac94c44fa2a9979e9c2a
Signed-off-by: Vanessa Rene Valderrama <vvalderrama@linuxfoundation.org>
Signed-off-by: Jessica Wagantall <jwagantall@linuxfoundation.org>
Signed-off-by: Jeremy Phelps <jphelps@linuxfoundation.org>