gevent 1.0 is not available for centos 6.x
gevent 1.0 is not available for centos 6.x

Change-Id: I350ca80eef5552c2c740c3a0e3e30f8f41ff8dea
Closes-Bug: 1460211
(cherry picked from commit d61173611e27a1f26d4f6ef67f21a14caecbad1f)

vpramo/contrail-packages,Juniper/contrail-packages,Juniper/contrail-packages,fpytloun/contrail-packages,tcpcloud/contrail-packages