Combine debug and verbose commandline options

Most of the openstack clients (for example nova) when --debug is specified it
shows the api calls the client is making. However, when debug is passed into
the neutronclient it shows exceptions that have occurred inside the
neutronclient. This patch combines verbose and debug to do the samething.

Change-Id: I6f2e0b17ffbe8fbfa77e26222dae32f5ab1e8866
Closes-bug: #1260489