remove access log middleware from the default paste pipeline

Implements: bp deprecated-as-of-icehouse
Change-Id: I1da036d998138964139c7fde3dde7ccb47f6a595
Use self.opt_in_group overrides

Use of self.opt_in_group makes option setting "sticky" even when
subsequent configuration files are loaded in. In some cases
(e.g. ``test_cert_setup.CertSetupTestCase``) the directly set
override (not using ``opt_in_group``) could be lost as test further
test cleanup patchsets were proposed. All identified direct
CONF object option setting has been replaced with use of
``opt_in_group``.

Change-Id: Iccd72003b61f775b71ea7402dc70eba1723d2336
bp: keystone-parallel-testing
Refactor Auth plugin configuration options

The auth plugin configuration can now either be specified by the
[auth] methods and [auth] <method name> options or as a class-name
as part of the [auth] methods option (e.g.
keystone.auth.plugins.password.Password). Both styles of auth
method specification can be used at the same time.  No two auth
plugins may register for the same auth method.

Each auth plugin must now define a 'method' attribute that specifies
the auth method it is registering for.

Tests have been modified to use a unified "method" name, this ensures
we are testing the appropriate code paths for auth methods rather than
relying on strings matching in all cases going forward.

Co-Authored-By: Brant Knudson <bknudson@us.ibm.com>
bp: keystone-parallel-testing
Change-Id: Icbb1d63d36726b8dbf7dfd8c6353fa30bbe490de
Merge "remove access log middleware from the default paste pipeline"
Merge "Refactor Auth plugin configuration options"