extension user_data v3 without alias prefix for request params

[Alex Xu]

user_data should be 'os-user-data:user_data'

also for xml namespace

    def server_create(self, server_dict, create_kwargs):
        create_kwargs['user_data'] = server_dict.get('user_data')

    def server_xml_extract_server_deserialize(self, server_node, server_dict):
        user_data = server_node.getAttribute('user_data')
        if user_data:
            server_dict['user_data'] = user_data

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/43399

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/43399
Committed: http://github.com/openstack/nova/commit/3e73b5cd1367174c9c1be813b4bd088766f94ab4
Submitter: Jenkins
Branch: master

commit 3e73b5cd1367174c9c1be813b4bd088766f94ab4
Author: He Jie Xu <email address hidden>
Date: Fri Aug 23 12:10:49 2013 +0800

    Add alias as prefix to request params for user_data v3

    fix bug 1215710

    DocImpact

    Change-Id: Iae48d2caefb1de46698c57712eae357c70c78997