Fix "Create network" explanation.
Fix "Create network" explanation.

Update the following sentence to indicate that the request body is optional:

  This operation does not require a request body. The tenant ID
  that you specify in the URI is the tenant that creates the network.

Change-Id: I456f8b018d47d0995d27eeabadee7dafa7f362ee
Closes-Bug: #1426227

Tesora/tesora-api-site,rackerlabs/api-site,Tesora/tesora-api-site,dreamhost/api-site,DonSchenck/api-site,Tesora/tesora-api-site,Tesora/tesora-api-site,rackerlabs/api-site,DonSchenck/api-site,openstack/api-site,openstack/api-site,rackerlabs/api-site,dreamhost/api-site,dreamhost/api-site,Tesora/tesora-api-site,rackerlabs/api-site,DonSchenck/api-site,openstack/api-site,Tesora/tesora-api-site,dreamhost/api-site,openstack/api-site,Tesora/tesora-api-site,dreamhost/api-site,dreamhost/api-site,DonSchenck/api-site,dreamhost/api-site,DonSchenck/api-site