Add in networks

Include the posibility to use extensions, for stuff like rackspace's
os-networksv2

my-nova:
  minion:
    mine_functions:
      network.ip_addrs: []
    startup_states: sls
    sls_list:
      - cloud.novaclient
  identity_url: 'https://identity.api.rackspacecloud.com/v2.0/'
  extensions:
    networks: os_networksv2_python_novaclient_ext
    virtual_interfaces: os_virtual_interfacesv2_python_novaclient_ext
  protocol: ipv4
  compute_region: IAD
  user: USERNAME
  tenant: TENANTID
  provider: nova
  api_key: APIKEY
  os_auth_plugin: rackspace
  wait_for_ip_timeout: 6000
Add network create function
Add network action to CloudClient

Allows for creating and deleting extra networks and the likes
Combine volume and network into extra actions
Add virtual interfaces
Clean up virtual interface attach
Document the new cloud module functions
Fix pylint issues
cloud client extra_actions needs a names variable
Merge pull request #12660 from gtmanfred/nova

Adding network and virtual_interface commands to the cloud module