Remove legacy diablo and essex test cruft

Remove the legacy cruft that is no longer used from diablo and
essex.

Change-Id: I4c00b12ef6d31c8387cdf12e58aed7416ede9f2d
Uses six.text_type instead of unicode

The unicode builtin doesn't exist in Python3.

Change-Id: Id13c8be7a016ec06d09cb45180dab64ade6f839c
Implements: bp keystone-py3kcompat
Remove unused method _create_metadata

The _create_metadata method in keystone.assignment.backends.ldap
isn't used or tested, so remove it.

Change-Id: I6479c8d294faab3ef57c4167a2f75db8a79c2ad4
Remove unused methods from AuthInfo

The lookup_user and _assert_user_is_enabled methods in
keystone.auth.controllers.AuthInfo aren't used or tested, so
remove them.

Change-Id: I9dedb918cdc19d659562f4caaf69de50a73deaff
Remove unused method _store_protocol

The _store_protocol method in
keystone.contrib.federation.backends.sql.Federation is no used,
tested, or documented, so remove it.

Change-Id: I9edf4cb36fa1f667813b4962da68a08fb277a332
Merge "Uses six.text_type instead of unicode"
Merge "Remove unused method _store_protocol"
Merge "Remove unused methods from AuthInfo"
Merge "Remove unused method _create_metadata"
Merge "Remove legacy diablo and essex test cruft"