3node failure due to ConflictingModificationAppliedException

This was seen in CSIT Netconf all job, causing a red dot.
See [0] from 2016-11-07 13:16:41,665.
But most all jobs usually pass without triggering this.

Possibly, a push of 39-pcep-provider.xml runs a code block aimed to create an empty pcep-topology, but the code block does not expect other member of cluster (also running the block) to interfere with its transactions.

[0] https://logs.opendaylight.org/releng/jenkins092/netconf-csit-3node-clustering-all-carbon/87/console.log.gz