Clustering : Recovery due to high snapshot count takes a long time.

Currently the Snapshot count is set to 100000.

This high number results in a high volume journal, recovery of which takes approximately 400secs

This was found when running the performance py script attached, using the following steps

1. Run a karaf distribution of the controller. OpenFlowPlugin should be just fine.
2. Install the feature odl-mdsal-clustering
3. Add 50,000 flows and remove 50,000 flows using the attached script.
/usr/local/bin/python flow_config_perf.py --nflows 500 --nthreads=10 --ncycles 10
4. Stop the controller
5. Start the controller
6. Checking the recovery times

We would need to find the optimal value for snapshot count so as to strike a balance between faster recovery time and not impacting performance by too frequent snapshotting.