Update bifrost to handle fedora as minor changes between
releases have been slightly breaking, and have gone largely
un-noticed since the bulk of bifrost users seem to use
centos or ubuntu.
Added a fedora 26 job to help enforce support moving forward.
Change-Id: I9a654b91edfa52321adccfa5df0c260eb0c9e487
Closes-Bug: #1695969
Closes-Bug: #1695968