[Plugins] Plugin v1.0 installation fails when -f flag is specified

Detailed bug description:

If a plugin in the version 1.0 is tried to be installed and it doesn't update an already installed plugin, when the user specifies the option -f in order to force the reinstallation, a python error is raised:

```
[root@fuel objects]# fuel plugins --install /tmp/lbaas-1.0.0.fp -f
DEPRECATION WARNING: The plugin has old 1.0 package format, this format does not support many features, such as plugins updates, find plugin in new format or migrate and rebuild this one.
Traceback (most recent call last):
  File "/usr/bin/fuel", line 10, in <module>
    sys.exit(main())
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/error.py", line 115, in wrapper
    return func(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/parser.py", line 266, in main
    parser.parse()
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/parser.py", line 143, in parse
    actions[parsed_params.action].action_func(parsed_params)
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/actions/base.py", line 62, in action_func
    method(params)
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/actions/plugins.py", line 88, in install
    results = Plugins.install(file_path, force=params.force)
  File "/usr/lib/python2.7/site-packages/fuelclient/objects/plugins.py", line 344, in install
    response = cls.register(name, version, force=force)
  File "/usr/lib/python2.7/site-packages/fuelclient/objects/plugins.py", line 299, in register
    return cls.update_or_create(metadata, force=force)
  File "/usr/lib/python2.7/site-packages/fuelclient/objects/plugins.py", line 454, in update_or_create
    url = cls.class_instance_path.format(id=resp['id'])
KeyError: 'id'
```

Steps to reproduce:

- Log into the fuel server
- Download any v1.0 plugin, eg

  wget http://plugins.mirantis.com/repository/l/b/lbaas/lbaas-1.0.0.fp

- Install the plugin

  fuel plugins --install /tmp/lbaas-1.0.0.fp

- Install the plugin again with -f

  fuel plugins --install /tmp/lbaas-1.0.0.fp -f

Expected results:

  The plugin is reinstalled

Actual result:

Traceback (most recent call last):
  File "/usr/bin/fuel", line 10, in <module>
    sys.exit(main())
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/error.py", line 115, in wrapper
    return func(*args, **kwargs)
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/parser.py", line 266, in main
    parser.parse()
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/parser.py", line 143, in parse
    actions[parsed_params.action].action_func(parsed_params)
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/actions/base.py", line 62, in action_func
    method(params)
  File "/usr/lib/python2.7/site-packages/fuelclient/cli/actions/plugins.py", line 88, in install
    results = Plugins.install(file_path, force=params.force)
  File "/usr/lib/python2.7/site-packages/fuelclient/objects/plugins.py", line 344, in install
    response = cls.register(name, version, force=force)
  File "/usr/lib/python2.7/site-packages/fuelclient/objects/plugins.py", line 299, in register
    return cls.update_or_create(metadata, force=force)
  File "/usr/lib/python2.7/site-packages/fuelclient/objects/plugins.py", line 454, in update_or_create
    url = cls.class_instance_path.format(id=resp['id'])
KeyError: 'id'

Reproducibility:

  Allways

Workaround:

  Doesn't exist

Impact:

  The user can not force the reinstallation of a v1.0 plugin

Description of the environment:

  Operation system: Linux fuel.domain.tld 3.10.0-229.20.1.el7.x86_64 #1 SMP Tue Nov 3 19:10:07
  Version of components: fuel 8.0.0

Aditional information:

In /usr/lib/python2.7/site-packages/fuelclient/objects/plugin.py, method update_or_create(), when resp status code is 409 ( Conflict ) and force flag is set, the put url is trying to be achieved using resp['id']

The problem is that, in that case, the resp has not such key. The 'id' key is in resp['message'] .

Proposed fix:

json.load(resp['message']) and get the 'id' from the resulting dictionary.