fakevirt: return hypervisor_version as an int instead of a string

The compute_nodes.hypervisor_version type in the database is an integer
not a string. This is only caught in postgres and not MySQL. Changing
the fakevirt driver to return the proper type allows for the
test_virt_drivers test to make check this for all drivers it currently
tests.

Change-Id: I25e4dba855b954a2451bced9a53172b51eb47238
Sync rpc fix from oslo-incubator

Sync the following fixes from oslo-incubator:

ef406a2 Create a shared queue for QPID topic consumers
e227c0e Properly reconnect subscribing clients when QPID broker restarts

Closes-bug: #1251757
Closes-bug: #1257293

Change-Id: I917c7a6e5cb64c6383e74d0fb6e095ad17d4d478
Merge "fakevirt: return hypervisor_version as an int instead of a string"
Merge "Sync rpc fix from oslo-incubator"