Return incorrect message in keypair-show and keypair-delete

[ugvddm]

Reproduce:
1.nova keypair-list

+----------+-------------------------------------------------+
| Name | Fingerprint |
+----------+-------------------------------------------------+
| root_key | 41:f3:fc:23:07:1d:99:cc:fd:e4:7a:a3:20:ba:78:25 |
+----------+-------------------------------------------------+

2.nova keypair-show root
ERROR: The resource could not be found. (HTTP 404) (Request-ID: req-542fa1da-0ab0-4624-b662-7d7c908508e2)

3.nova keypair-delete root
ERROR: The resource could not be found. (HTTP 404) (Request-ID: req-2f8587a3-ee5e-4134-ba5d-a2b3f0968cbc)

expected:
1.nova keypair-show root
ERROR: No keypair with a name or ID of 'root' exists.
2.nova keypair-delete root
ERROR: No keypair with a name or ID of 'root' exists.

[Openstack Gerrit (openstack-gerrit)]

Fix proposed to branch: master
Review: https://review.openstack.org/87828

[Openstack Gerrit (openstack-gerrit)]

Fix proposed to branch: master
Review: https://review.openstack.org/88526

[Openstack Gerrit (openstack-gerrit)]

Reviewed: https://review.openstack.org/88526
Committed: https://git.openstack.org/cgit/openstack/python-novaclient/commit/?id=fdd59e142a69d02123ad5b8522ba0e75c731e02f
Submitter: Jenkins
Branch: master

commit fdd59e142a69d02123ad5b8522ba0e75c731e02f
Author: Zhengguang <email address hidden>
Date: Fri Apr 18 15:15:48 2014 +0800

    Fix the incorrect return messages in keypair show and delete

    When we delete or show a keypair, if the keypair doesn't exist,
    we'll get "The resource could not be found.(HTTP 404)", this
    patch will change it to "ERROR: No keypair with a name or ID of
    'keypair_name' exists."

    Change-Id: Ifebd8d2213c327f3d3fdd672207170aebbe1bb40
    Closes-Bug: #1307338

[Openstack Gerrit (openstack-gerrit)]

Reviewed: https://review.openstack.org/87828
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=6cd183a4bac7ae79bca380c960686ea33892f066
Submitter: Jenkins
Branch: master

commit 6cd183a4bac7ae79bca380c960686ea33892f066
Author: Zhengguang <email address hidden>
Date: Wed Apr 16 09:27:46 2014 +0800

    Fix the explanations of HTTPNotFound for keypair's API

    Gets the "explanation" from HTTPNotFound exception and returns
    correct message. the commit Ia784e09cda986a421e83c2820dfd0a2267867cdd
    has fixed this kind of bug already, but this bug is remained.

    Closes-Bug: #1307338
    Change-Id: I6811eecba86938e4253f437b7677cb7e4468fd67