Fix UnicodeDecodeError's in the functional tests
Fix UnicodeDecodeError's in the functional tests

While running the functional tests some UnicodeDecodeErrors are
triggered since the logger can't properly print some binary characters
that are provided in both the requests (When PUTing a secret) and the
responses (when GETing a secret). So this catches those errors and
sets the logged string to be properly printed, which helps debugging
for errors.

Change-Id: Ia61e4fc0891775c15d725ac8b2d5178e31ec9bf1

openstack/barbican,MCDong/barbican,cneill/barbican,jmvrbanac/barbican,MCDong/barbican,jmvrbanac/barbican,openstack/barbican,cneill/barbican,cloudkeep/barbican,cloudkeep/barbican