Add Savanna client for node group templates

It adds data_processing service with simple Savanna client that currently
supports only CRUD operations with node group templates.

Change-Id: Ic96ae88fcfe164f4953013a2d4433bc9c9bf6c6d
scenario/network_basic_ops: reassociate floating-ip

check that a detached FIP can be associated with a new VM and make sure
it is not associated with the old VM by assigning a different keypair to each
new VM so that ssh connection cannot be made without the right keypair

Change-Id: Ib535aa66638a3e7f2f1549b6e7a21a160377df6a
Merge "Add Savanna client for node group templates"
Merge "scenario/network_basic_ops: reassociate floating-ip"