Boron: occasionally l3vpn routes are not advertised from odl to exabgp

From time to time the job https://jenkins.opendaylight.org/releng/view/bgpcep/job/bgpcep-csit-1node-userfeatures-all-boron/ failes. See builds #384 and #388.

The only job https://jenkins.opendaylight.org/releng/view/bgpcep/job/bgpcep-csit-1node-userfeatures-only-boron/ does not fail the same way.

The suite 010 Bgp Functional L3Vpn fails in L3vpn_Ipv4_From_Odl test case and since then all fails, but the first exceptions in the log appear while configuring application peer.

https://logs.opendaylight.org/releng/jenkins092/bgpcep-csit-1node-userfeatures-all-boron/388/archives/karaf.log.gz

2016-12-15 18:47:11,883 | INFO | h for user karaf | command | 498 - org.apache.karaf.log.command - 3.0.7 | ROBOT MESSAGE: Starting test Configure_App_Peer