Enables Debugging Mode for Neutron Agents

According to CONFIG_DEBUG_MODE, this patch will enable debug mode for the
Neutron Agents.

Change-Id: I0c169f6b9cb28afed608b36bae47fe99a62ce903
Fixes: rhbz#1090785
Setup neutron l2 plugin configs only on neutron api nodes

Closes-Bug: rhbz#1113472
Change-Id: I4b28162b922393ee25595188fbb6681a271fc20a
Connect bridge with interface only on network hosts

Change-Id: I4dad33a12c555bab37ae8373823eac4603a57430
Merge "Enables Debugging Mode for Neutron Agents"
Merge "Connect bridge with interface only on network hosts"
Merge "Setup neutron l2 plugin configs only on neutron api nodes"