Need to restart contrail api if ifmap server restarted

[Édouard Thuleau]

If the ifmap was restarted, all graph is lost as it's a in-memory db. So the vnc api server also need to be restarted to reseed all graph.

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/22802
Submitter: ?douard Thuleau (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/22802
Committed: http://github.org/Juniper/contrail-controller/commit/083616059840e1dc10631deb21b6064970a1e013
Submitter: Zuul
Branch: master

commit 083616059840e1dc10631deb21b6064970a1e013
Author: Édouard Thuleau <email address hidden>
Date: Wed Aug 3 18:38:19 2016 +0200

Resync ifmap graph when restart

1/ When a ifmap server restarting, the api reseed all graph with data
fetched from database without the need to restart vnc api server.
2/ If the connection between the api and ifmap server gone down, the api
buffered messages in the ifmap sending queue and send them when the
connection comes up again. If the buffered queue was exceeded, requests
continue to enqueue in the rabbitmq until ifmap server comes up again.

Also fix an issue in the db-loader script to support new keyspace dict
and add an option to not load zookeeper database.

Change-Id: I8123deed561c9344b854e65b60b5735a2ba4d19e
Closes-Bug: #1622101