Distributions provide packages for the OpenStack services so we add
support for using these instead of the pip ones.
Depends-On: I5a78e2120e596d36629b4ba978b2b5df76b149b0
Depends-On: Ib64dcbc960df7d369d202ce8cf7bdc29b3ee0e0a
Depends-On: Id9dd2dea146709414ab9ce8d439f1587e6776fd4
Depends-On: I2ba89e25c0010c9a5b515a3d0c9c731b30876e74
Depends-On: I0442b0aa94c3d0882d1118ad0c824d123bd21c88
Change-Id: I26848678dd07a409ef3e159cffb4ba6f0a228ab4
Implements: blueprint openstack-distribution-packages