Move REST req/resp logging from DEBUG to TRACE
Move REST req/resp logging from DEBUG to TRACE

Since the adapter core of pypowervm has matured, the DEBUG logging level
for pypowervm has been pretty much useless, as it generates a huge
amount of content - particularly the payload of every REST request and
response.  This obscures the other, more useful pypowervm debug logging
(as well as other useful logging at any level from other sources) in a
mess of noise, and has resulted in the DEBUG level falling into disuse.

This change set converts these few logging statements - those dealing
with REST request/response content - from DEBUG to TRACE.  This should
allow consumers to set pypowervm's default logging level to DEBUG and
have it be usable.

Change-Id: Id5c3a8fb40d29b5a1d8b3280ed40beb2dda31718

pypowervm/pypowervm,powervm/pypowervm