remove unused, commented-out ldap domain attributes
rename ldap tenant_* attributes to project_*
update keystone.conf comments

there should be no functional changes in this commit
redis confs moved to their own section [matchmaker_redis]
removed keystone.middleware.ec2_token options
removed keystone.openstack.common.lockutils options
New/Removed/Changed options in Juno's keystone.conf

Removed options (we were not modifying the default values):
- memcache max_compare_and_set_retry
- onready
- allowed_rpc_exception_modules
- [cache] use_key_mangler

New options:
- public_workers, admin_workers, strict_password_check
- ldap connection pooling, debug_level, user_enabled_invert
- memcache connection/pooling options
- [token] hash_algorithm
- qpid_receiver_capacity
- [database] slave_connection
- [endpoint_policy] driver
- [catalog] caching, cache_time
- [identity_mapping] driver, generator, backward_compatible_ids

New section: [saml]

Default control_exchange changed from 'openstack' to 'keystone'
Merge pull request #249 from mapleoin/config-juno

Update keystone.conf to juno