Encode consoleauth token in utf-8 to make it a str

This is needed for memcached backend, because the key cannot be a
unicode object in any of the exposed functions.

Fixes bug 1164784

Co-authored-by: Stanislaw Pitucha <stanislaw.pitucha@hp.com>

Change-Id: Ieb1429116d96eefe97564fe92631063dc16117cb
(cherry picked from commit 6dadf73305c0a3d779dd625a8349b4a7341df18d)
Merge "Encode consoleauth token in utf-8 to make it a str" into stable/grizzly