Modify the manage command prompt information

[zhongjun]

Modify the manage share command prompt information
1. change host@driver[#pool] to host@driver#pool, because pool is a required parameter.
2. change <share_type> to <share-type>, Make this consistent with 'manila create' command prompt information.
3. Add example for export_path.

root@ubuntu:~# manila help manage
usage: manila manage [--name <name>] [--description <description>]
                     [--share_type <share_type>]
                     [--driver_options [<key=value> [<key=value> ...]]]
                     <service_host> <protocol> <export_path>

Manage share not handled by Manila.

Positional arguments:
  <service_host> manage-share service host: some.host@driver[#pool]
  <protocol> Protocol of the share to manage, such as NFS or CIFS.
  <export_path> Share export path.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/209400
Committed: https://git.openstack.org/cgit/openstack/python-manilaclient/commit/?id=f0c66851e38aefd5674dc635126b513b58fbca63
Submitter: Jenkins
Branch: master

commit f0c66851e38aefd5674dc635126b513b58fbca63
Author: zhongjun <email address hidden>
Date: Wed Aug 5 16:28:58 2015 +0800

    Modify the manage command prompt information

    -- Change host@driver[#pool] to host@driver#pool,
       because pool is a required parameter.
    -- Change <share_type> to <share-type>, Make this
       consistent with 'manila create' command prompt
       information.
    -- Add example for export_path.

    Closes-Bug: #1481611
    Change-Id: I4991389a3b0666eea5fb801071bb9b9557519e80