* Agent changes for policy based vrf assignment
Don't make TaskScheduler recycle the task when WorkQueue is disabled.

The previous behaviour didn't let tests use task_util::WaitForIdle()
after disabling a WorkQueue since the QueueRunnerTask was constantly
being recycled.
Make StartRunnerFunction behave similar to disabled_.
* Address review comments
1. Rename --conf_file  argument to --config_file
2. Use cout instead of LOG until the Logging Module is initialized
3. Continue parsing even when there is error while parsing VHost IP
4. Add default values in command line parser initialization list
Merge pull request #651 from Juniper/ashoksr_fixes

Fix the following issues
Merge pull request #615 from naveen-n/master

* Agent changes for policy based vrf assignment
Remove zc-zookeeper-static dependency as it is not used
Merge pull request #652 from safchain/remove-zc-zk-static

Remove zc-zookeeper-static dependency as it is not used
Merge pull request #653 from Juniper/nsheth_work_queue_disable

Nsheth work queue disable