* Agent changes for policy based vrf assignment
analytics support in packages; .conf file for analytics-api; renaming of executables
missing defaults in help
Atomic ref update

This commit provides atomic ref update so that multiple api server updating the same ref list can update it without overwriting each other's changes.
We are creating a new POST API 'ref-update' that can be used to update an individual reference. An accompanying change in generateDS.py is required.
Allow ref-update with just fq-name also
1. Track the zookeeper state
2. Exit if the connection is LOST and
3. Pause the master if connection moves to SUSPENDED. (Since master could have switched)
    A. Changed schema and svc mon to wait in main loop.
    B. Discovery change is pending. To be handled in
    C. API server doesn’t accept any request (PUT, POST and DELETE) if not connected to Zookeeper. Only accept GET request. In this case we don’t query zookeeper.
4. Connect to all zookeeper server instead of connecting to local zookeeper server.(Pass list of server while creating KazooClient)
5. Change the retry logic with KazooRetry. Kazoo client has logic to reconnect automatically till SessionExpires(LOST). Instead of reconnecting from our application logic, use KazooRetry to retry zookeeper operation.
Update timer to handle delete_on_complete
Merge pull request #628 from Juniper/atomic_ref_update

Atomic ref update
Add more RoutepathReplicator tests for changes in instance RouteTarget.
Make parse error handling in BgpConfigParser less forgiving.

Note that BgpConfigParser should be treated as test code rather
than production code. Hence it's better to flag errors and fail
instead of ignoring them. Allows errors in tests to be detected
more easily.

Fix a couple of tests that had bad configuration.
Merge pull request #638 from Juniper/nsheth_config_parser

Make parse error handling in BgpConfigParser less forgiving.
fix for 2830: Handle empty client entry
Merge pull request #639 from Juniper/dsetia-ml-disco2

fix for 2830: Handle empty client entry
Remove dead code.
Merge pull request #641 from Juniper/nsheth_dead_code

Remove dead code.
vnswad now take configuration in the standard ini format.
Default configuration file is read off /etc/contrail/vnswad.conf

One can override the values from the config file through command line option.
The list of vnswad configuration parameters are specified in src/vnsw/agent/test/vnswad.conf
Merge pull request #637 from Juniper/nsheth_instance_rtarget_update2

Add more RoutepathReplicator tests for changes in instance RouteTarget.
Review comments
Merge pull request #636 from haripk/master

Update timer to handle delete_on_complete
Add tests to simulate failures in BgpSessionManager::CreateSession.

Simulate socket open failure in BgpSessionManager::CreateSession.
Simulate unknown failure in BgpSessionManager::CreateSession.