Keep the CENGN copy of yum.repos.d and rpm-gpg-keys updated
relative to the master copies found in stx-tools.
It is not a blind copy. Rather we add new repo files and
repo id's but never delete old ones.
If a pre-existing repo id has it's url change,
e.g. mirror.centos.org -> vault.centos.org
we keep a record of the old url under a modified repo id.
This update also relocates a number of common functions
into utility scripts that can be sourced.
Story: 2003906
Task: 26785
Change-Id: I2b5ef46ad7cfe2a3575a3d3d7c91a9511da5ee3c
Signed-off-by: Scott Little <scott.little@windriver.com>
e3c49d3389