One of the community goals for Stein is to implement a command-line
tool for operators that runs programmable checks that might impact
upgradability.
This commit lays down the basic structure for the upgrade checks and
ties it up to `glance-status` command.
Change-Id: I7fcf5235a76d15dbcb2c49255bc26c2b586cd71c
Story: 2003657
Task: 26135