Support format for msgpack < 1.0 in token formatter
Support format for msgpack < 1.0 in token formatter

msgpack v1.0 changed its data format [1] and during a rolling upgrade, attempts
to unpack cached tokens with old data format with the new default raw=False
result in the following error:

  UnicodeDecodeError: 'utf-8' codec can't decode byte 0x87 in
  position 3: invalid start byte

This passes raw=True to support backward-compat with the old format
until we are guaranteed to have msgpack >= 1.0 in the N-1 release of
a rolling upgrade.

Closes-Bug: #1891244

[1]
https://github.com/msgpack/msgpack-python/blob/v1.0.0/README.md#major-breaking-changes-in-msgpack-10

Change-Id: I6c61df6c097fef698c659c79402c4381ec7f3586

mahak/keystone,openstack/keystone,openstack/keystone,openstack/keystone,mahak/keystone,mahak/keystone