Add authenticate method to oauth code

Forgot to add one last method when I initially checked in
the first set of code; the authenticate method will return an
actual keystone token that the user may now use.

Also, I added some changes to other methods because the client
has been updated.

Change-Id: Ie2707689e0df1fb1bc92177f932baf23fe1ca920
Remove api = apiName calls from each method

As discussed in https://review.openstack.org/#/c/36352/ for each
command, we were setting api = identity or volume... etc,
this was for an old way of calling commands that are is no longer
used.

Also removed openstackclient/common/command.py

Change-Id: I2705f35d343f2ae729dc22d6aed0b852b2f8ca19
Add show limits command

* This is a combination of the compute and volume API limits as they are
  very similar.  As such, the command lives in a new command group
  'openstack.common' that is unversioned.
* Implements 'limits show [--absolute|--rate]

Updated for https://review.openstack.org/#/c/36772/

Bug: 1172057

Change-Id: I2bd181cd0d098f7143360ae67944c2f221379af5
Merge "Add authenticate method to oauth code"
Update openstack-common.conf format

Change-Id: Ifa6718331d3da91f0e9515a809484808bd6317f9
Add --catalog to service show

Shows endpoints from the service catalog rather than the system services.

Change-Id: I842916af9f7c0a76c4d3e27e419bf0fec059ec78
Add list and delete authorizations for oauth commands

* List user authorizations
* Delete user authorization
* Grouped the commands with oauth prefix

Change-Id: I032ffa25181aad0fb4689f69cdca5a7adc6e29f1
Merge "Add show limits command"
Add quota commands

* Add quota set and quota show commands; these work on both
  the compute and volume APIs
* Add the --class variation on the above commands

Note: this replaces the existing volume-only quota commands and eliminates quota list

Blueprint: cinder-client
Bug: 1172064

Change-Id: I766d40e410e48f05e36e17e567a4f01a9411b40e
Merge "Add --catalog to service show"
Complete Image v1

* Add v1 versions of image delete, list, save, set, show
* Change default Image API to v1

Rebased for https://review.openstack.org/#/c/36772/

Change-Id: Ie2bfe660aac8a0fcf651c67fd1ea4842e76ce377
Merge "Add list and delete authorizations for oauth commands"
Merge "Add quota commands"
Add aggregate commands

* Add aggregate: add host, create, delete, list, remove host, set, show

* Add list --long option
* Filter 'availability_zone' from the metadata fields
* Rename 'metadata' column to 'properties' in all output

Bug: 1172032
Blueprint: nova-client

Change-Id: Icd408c2b34af07f5102f53d3778d8546952a12c5
Merge "Add aggregate commands"
Merge "Complete Image v1"