Fix for sahara CLI
Fix for sahara CLI

Sahara CLI did not work because 'safe_encode' and 'safe_decode'
methods have been moved from 'oslo.utils.strutils' module
to 'oslo.utils.encodeutils' module

Change-Id: Ica8cf4e8ec058fa0764e69945609f2a19effb840
Closes-bug: #1409432

openstack/python-saharaclient