KeypairsClient() not specifying service name in setup.

[Adam Gandelman]

The keypairs JSON Nova client does not specify the keystone service entry when setting up its RestClient(). Since this client gets instantiated with every nova test, all tests currently fail:

# nosetests -xvd -s tempest/tests/test_extensions.py
ERROR

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ERROR: test suite for <class 'tempest.tests.test_extensions.ExtentionsTest'>
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Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/nose/suite.py", line 208, in run
    self.setUp()
  File "/usr/lib/python2.7/dist-packages/nose/suite.py", line 291, in setUp
    self.setupContext(ancestor)
  File "/usr/lib/python2.7/dist-packages/nose/suite.py", line 314, in setupContext
    try_run(context, names)
  File "/usr/lib/python2.7/dist-packages/nose/util.py", line 478, in try_run
    return func()
  File "/root/tempest/tempest/tests/test_extensions.py", line 11, in setUpClass
    cls.os = openstack.Manager()
  File "/root/tempest/tempest/openstack.py", line 52, in __init__
    self.config.nova.tenant_name)
  File "/root/tempest/tempest/services/nova/json/keypairs_client.py", line 10, in __init__
    auth_url, tenant_name)
  File "/root/tempest/tempest/common/rest_client.py", line 17, in __init__
    tenant_name)
  File "/root/tempest/tempest/common/rest_client.py", line 74, in keystone_v2_auth
    raise exceptions.EndpointNotFound(service)
EndpointNotFound: Endpoint not found
Details: admin

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Ran 0 tests in 4.235s

Fix submitted before reporting here: https://review.openstack.org/#change,3330