Increase the retry_count to connect tot VncApi from 10 to 30

contrail-api takes more than 10 sec to listen on 9100, If neutron plugin tries to
connect to Vncapi before that on 8082(haproxy), it gets 503. This happens in a single node setup
after reboot, Fixing it by increasing the retires to 30.

Change-Id: Idfd1c9e92a26468771d0375dfb252cb920b3f82c
Partial-Bug: 1379640
Merge "Increase the retry_count to connect tot VncApi from 10 to 30"