Don't expose X-Auth-Token in ceilometer CLI

Ceilometer CLI exposes X-Auth-Token in debug mode. This patch
replaces X-Auth-Token's value with '{SHA1}<sha1oftoken>'. Some
credentials are exposed by keystoneclient as ceilometerclient
uses keystoneclient to authenticate, it will be fixed in bug:
100414.

Change-Id: Ia6364314e4b4d26301f974582c0c2ba34b054c86
Partial-Bug: #1327019
Merge "Don't expose X-Auth-Token in ceilometer CLI"