Refactor get role for trust

When retrieving a role, exploit the check role function.

Change-Id: Id39740f8c531d1ea109f3ce1a1e344ac2a2fe7a1
Syncing policy engine from oslo-incubator

Syncing policy module - commit a53c4dc
Includes patch 0da5de6 implementing Blueprint policy-constant-check

python update.py --nodeps --base keystone --dest-dir ../keystone/ --modules policy

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Adds the ability to check any resource's field against a constant
(literal, or string) in the policy.json file.

For instance, I can ensure that only users with field `enabled` set to
False can be deleted with the following rule:
"identity:delete_user": "False:%(target.user.enabled)s",

Or that only the `Member` role can be granted:
"identity:create_grant": "'Member':%(target.role.name)s",
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Change-Id: I054271306f20aac47ce5e9dac594bc1989fee56d
Implements: blueprint policy-constant-check
Remove copyright from empty files

According to policy change in HACKING:
http://docs.openstack.org/developer/hacking/#openstack-licensing
empty files should no longer contain copyright notices.

Change-Id: I65e85baf72cf1a413c4b4c8c478587246d4c319a
Closes-Bug: #1262424
Remove s3_token functional tests

The s3_token middleware was moved to keystoneclient but the tests
were left to ensure backwards compatibility. The tests have passed
since then and the keystoneclient of the s3_token middleware has
already diverged that causes the tests to fail.

The functional tests are removed and replaced with a test to
ensure that the symbols are forwarded properly.

bp s3-token-to-keystoneclient

Change-Id: Ie1cea741d33400eaa4d4afc7206a3ba1db9a4573
Merge "Remove copyright from empty files"
Merge "Syncing policy engine from oslo-incubator"
Merge "Refactor get role for trust"