shell: make client works with default Gnocchi installation

This sets the default auth mode to "basic" (like Gnocchi itself) and the
default value for user and endpoint to something that make it work without
setting anything in simple scenario.

Basically, it makes it work by default in many simple cases.

Change-Id: I7f2dab85f97808f5245d80fd8e04cc535d1f3f6f

gnocchiclient/auth.py

@@ -107,9 +107,11 @@ class GnocchiBasicLoader(loading.BaseLoader):
         options = super(GnocchiBasicLoader, self).get_options()
         options.extend([
             GnocchiOpt('user', help='User', required=True,
+                       default="admin",
                        metavar="<gnocchi user>"),
             GnocchiOpt('endpoint', help='Gnocchi endpoint',
                        dest="endpoint", required=True,
+                       default="http://localhost:8041",
                        metavar="<gnocchi endpoint>"),
         ])
         return options

gnocchiclient/shell.py

@@ -132,7 +132,7 @@ class GnocchiShell(app.App):
             help='Defaults to env[GNOCCHI_API_VERSION] or 1.')
         loading.register_session_argparse_arguments(parser=parser)
         plugin = loading.register_auth_argparse_arguments(
-            parser=parser, argv=sys.argv, default="password")
+            parser=parser, argv=sys.argv, default="gnocchi-basic")
 
         if not isinstance(plugin, (auth.GnocchiNoAuthLoader,
                                    auth.GnocchiBasicLoader)):