fixing the issue with pbr upgrade during setup_test_env also adding requests==2.3.0 this is required as dependency in pyvmomi install(in future in mainline). The latest request has an issue ,pip command won't work on latet requests==2.7
fixing the issue with pbr upgrade during setup_test_env also adding requests==2.3.0 this is required as dependency in pyvmomi install(in future in mainline). The latest request has an issue ,pip command won't work on latet requests==2.7

Change-Id: I06bc4a244be5bf1a9de4703c8d1da465164949da

Juniper/contrail-fabric-utils,Juniper/contrail-fabric-utils