Add python27 job to nova-specs

As of I1c15282e166fb3fe2e60fcf063a6cd822a3411ff nova-specs has a unit
test that we want to gate on. Since nova-specs isn't a deliverable repo
or part of the integrated release, we don't care about python26
compatibility.

Change-Id: I08f131a0a00f64f193e25b4df7fa56d53b41f510
Merge "Add python27 job to nova-specs"