Test / 02 Bgp Vpnservice / Some improvements

Some enhancements are wished on bgp_vpnservice test suite:
From recent test result, 3 new testing should be welcome in that test suite.

This issue is related to testing improvement.
Not related to fixing the issue from [0]

====================================
a recent test suite result related to bgp vpnservice in [0]

• the test "Verify BGP Neighbor Status" failed, whereas the BGP peer has been established
  it appears that the error is related to prefix list not available:

=> the test should focus on establishment
=> a new test should be added , that checks for the prefix entry.

• the test fail, and it is hard to understand what happens
  bgpd# ' does not contain '5.5.5.2'
  Further analysis in karaf.log.gz file seem to indicate the following

2017-08-22 12:14:19,696 | ERROR | pool-43-thread-1 | BgpConfigurationManager | 294 - org.opendaylight.netvirt.bgpmanager-impl - 0.5.0.SNAPSHOT | Replay:addVrf() 2200:2 received exception:
org.apache.thrift.TApplicationException: BGP RD (null) not configured

=> an other test should be created, and that checks that the incoming ODL configuration is well configured, especially for VRFs

ex:
show running
configure terminal
vrf rd 2200:2
...
shows that vrf 2200:2 is well configured

the non presence of that line shows the contrary.

[0] https://logs.opendaylight.org/releng/jenkins092/netvirt-csit-hwvtep-1node-openstack-newton-upstream-transparent-nitrogen/122/robot-plugin/log.html#s1-s3-t3