Skip IPv6 tests if IPv6 is not supported.

Change-Id: I8aac6b0bc675a223213348324ac8305907eb0028
public_endpoint & admin_endpoint configuration

Today we can use these configuration values to avoid having to guess
keystone's own endpoint URL from the service catalog backend, which may
contain more than one identity endpoint.

This is also the first step towards adding self-relational links to the v3 API.

Change-Id: I375ac0d1f9581592e437c67c17bf32022f652f66
Fix role delete method in LDAP backend.

It used to delete all roles in all tenants.

Change-Id: I9283a28422559a33b92ee9c975fc7a8e299b8f21
Merge "public_endpoint & admin_endpoint configuration"
Merge "Fix role delete method in LDAP backend."
Merge "Skip IPv6 tests if IPv6 is not supported."