Moderately large numbers of intents do not generate correct number of FlowMods

To recreate:

1. Create topology with redundant paths, allocated across three ONOS instances. Topology for this test is generated with attached ``solar.py'' using `onos-start-network`, and switches are allocated using `ovs-vsctl set-controller` in the Mininet VM.
2. Install 100 intents (minimum 50) along a path (6 hops), using attached ``path-install.sh''.
3. Break link along path, causing path to switch to alternate (7 hop) route. Link is brought up/down using script for automating this and packet capture of the control channels, ``measure.sh''.

For 50 intents, step 3 should generate 700 FlowMods (7 * 50 * 2), but will often fall short. This mismatch becomes consistent for 100 intents and higher.

notes:

• .pcap file is attached for 50-intent case, for an instance connected to two switches (which therefore should contain 200 FlowMods if correctly working)
• the attachment points in ``path-install.sh'', and the IP addresses in the scripts, may need to be modified according to your test environment.
• attached cell environment was used for this test.