Branch-specific test infrastructure
Branch-specific test infrastructure

Issues:
Fixes #506

Problem:
Automated regression infra currently uses one branch and tracks release-specific operations via filenames containing the OpenStack release. Migrate to using a branch per release to be consistent with product r    epos.

Analysis:
Add branch (OpenStack distro) when cloning test infra installation scripts.

Tests:
Manual confirmation that install_test_infra cloned the correct code/branch.

jlongstaf/f5-openstack-lbaasv2-driver,jputrino/f5-openstack-lbaasv2-driver,F5Networks/f5-openstack-lbaasv2-driver,richbrowne/f5-openstack-lbaasv2-driver,richbrowne/f5-openstack-lbaasv2-driver,mattgreene/f5-openstack-lbaasv2-driver,jputrino/f5-openstack-lbaasv2-driver,jlongstaf/f5-openstack-lbaasv2-driver,F5Networks/f5-openstack-lbaasv2-driver,mattgreene/f5-openstack-lbaasv2-driver