Make novnc test compatible with RFB3.3
Make novnc test compatible with RFB3.3

Please refer to:
https://tools.ietf.org/html/rfc6143#appendix-A.1
The RFB negotiation is different for RFB 3.3.

Change-Id: I506e7a90348324c36a06525e74c0c39ed2547d4c
Closes-Bug: 1672242

cisco-openstack/tempest,masayukig/tempest,openstack/tempest,vedujoshi/tempest,Juniper/tempest,masayukig/tempest,Juniper/tempest,openstack/tempest,vedujoshi/tempest,cisco-openstack/tempest