provisioning: retry with limit when service <x> status errors
provisioning: retry with limit when service <x> status errors

Observed following transient case in CI where status gave an error when checking
right after supervisor start. Handle this with warn so retry loop works.
2015-04-29 11:52:20:572819: [root@192.168.0.38] out: [rabbitmq-server] started by supervisor config.
2015-04-29 11:52:20:773421: [root@192.168.0.38] out: [localhost] local: sudo service contrail-api status
2015-04-29 11:52:20:773603: [root@192.168.0.38] out:
2015-04-29 11:52:21:174819: [root@192.168.0.38] out: Fatal error: local() encountered an error (return code 2) while executing 'sudo service contrail-api status'
2

Change-Id: Iea896a66e948d91085bf08e728c9e7e2d04c8e8b

Juniper/contrail-provisioning,Juniper/contrail-provisioning