In Mitaka Glance v3 was moved to stand alone service [1] - now
it's called Glance Artifacts Repository (Glare).
This patch adds appropriate service managing, package installation,
configuration and related spec tests.
[1] I5b7bd4cdcc5f2a40fc4a5f74bcc422fd700c4fb0
Change-Id: I3371d1d57486e79ccfae565417f2195d3ae66bc9
Closes-bug: #1555697