Add the ability to pass fields with the
auto-allocated-topology-show command to support the
dry-run validation option of the API.
With dry-run the CLI result is "Pass" or the error message
from the response.
Rename the client binding from show_ to get_. Also provide a
client binding for validating the auto-allocation requirements.
Partially-Implements: blueprint get-me-a-network
DocImpact: Add info about dry-run to the auto-allocate section
in the networking guide.
Change-Id: Ieba6f3cde23a8a93067b8239b096d5103f6a3128
d3f13f4c20