Pass full principal when creating a kerberos AP_REQ

Bug: 907297
Improve accuracy of beakerd metrics reporting

- unit tests for check_virtualisibility()
- beakerd metrics tests are now more stringent
- check_virtualisibility() now defined only on MachineRecipe
- check_virtualisibility() also checks host_requires
- all recipe queue metrics now defined only for MachineRecipe

Bug: 902659
Change-Id: I3d77209d8511cf8b34132be6e722dc479fea336e
Only try oVirt for x86_64 recipes

Bug: 907307
Change-Id: I385272c3a1dea9fdd191684605a97e0cbff02068
Merge "Improve accuracy of beakerd metrics reporting" into release-0.11
Merge "Only try oVirt for x86_64 recipes" into release-0.11
Merge branch 'release-0.11' into develop