Neutron LBaaS: Load Balancers Client

* client for CRUD actions for a loadbalancer
* includes metatests for de/serialization of json/xml

Change-Id: Ibcc3b38bf39189afffaddef4654e403b87c0700e
Neutron LBaaS: Listeners Client

* client for listeners CRUD actions
* includes metatests for json/xml de/serializtion

Change-Id: Iac831581bd16936cbcb2e7ab8261b349de4bbf26
Merge "Neutron LBaaS: Load Balancers Client"
Merge "Neutron LBaaS: Listeners Client"