Adds deleting scenarios for Neutron:

- NeutronNetwork.create_and_delete_networks

- NeutronNetwork.create_and_delete_subnets

- NeutronNetwork.create_and_delete_ports

blueprint benchmark-scenarios-for-neutron

Change-Id: I585b76935644712c019a9d5502637fbad6d4d2f0
Updated from global requirements

Change-Id: Ib4377d74f62035f6462669cdd257ae0f9140a637
Mock open to prevent file creation

Some unit tests does create files in root of project

Change-Id: I9b9907177ad1d25142d85538a727a5e8eab99df0
Update rally neutronclient ca_cert option

Recently the neutronclient constructor cacert parameter
has been changed to ca_cert causing rally gate failures.
Fixed it.

Neutron-client Change Id: I9d0395d405b9fbe4db08ad3727f9413be7b82811
Change-Id: Id616d0f315f247d4f89ee779c4424bc93cc208db
Closes-Bug:#1353268
Merge "Mock open to prevent file creation"
All scenario runs time measurement

  Partially implements: blueprint collect-runtime-duration

Change-Id: I2708a5f915d5b13948f50dfad26b2463b9d5249b