Make RabbitMQ default AMQP provider
Make RabbitMQ default AMQP provider

Icehouse releases will have RabbitMQ as the default provider of AMQP broker

Change-Id: Id24bdb975f0558d0d08262ae0e4feede722ae422

stackforge/packstack,palmer159/openstack-test,mahak/packstack,openstack/packstack,fr34k8/packstack,fr34k8/packstack,palmer159/openstack-test,openstack/packstack,imcsk8/packstack,xbezdick/packstack,mahak/packstack,stackforge/packstack,xbezdick/packstack,imcsk8/packstack,fr34k8/packstack,stackforge/packstack,xbezdick/packstack,palmer159/openstack-test,openstack/packstack,imcsk8/packstack,mahak/packstack