This change aims to add the foundations for CentOS support
on manila-image-elements.
In this patch-set, the following has been modified
- Added elements for manila-centos-minimal
- Added elements for centos-nfs
- Added elements for centos-cifs
- Renamed all elements for the different protocols to distro-protocol
to facilitate automation
- Modified the main script to take the distro param
Follow-up patches will add centos-based elements
for all other protocols supported.
Change-Id: Ie1469a8b3973b9a15c3fa27688df3b7e7e8da688
Partial-Bug: #1675538
375ddd1e9e