Remove name parameter from cell export

Initially the idea was to have for each cell export information
for the additional cell to deploy. The name of the new cell
is provided to the export command to create the export file
name, if not specified via --output-file.
Since the exported information is not in all cases specific to
the new cell and can be shared with multiple cells, it does
not make sense to have the new cell name as a required parameter.
Lets remove the name parameter is it is right now that the
export information file name is generic to be used for multiple
cells.

Change-Id: If8b15fd206a32dbd5b2edb1cd500f4e2151313d9
(cherry picked from commit f10842848b)

tripleoclient/v1/overcloud_cell.py

@@ -32,9 +32,6 @@ class ExportCell(command.Command):
 
     def get_parser(self, prog_name):
         parser = super(ExportCell, self).get_parser(prog_name)
-        parser.add_argument('name', metavar='<cell name>',
-                            help=_('Name of the stack used for the additional '
-                                   'cell.'))
         parser.add_argument('--control-plane-stack',
                             dest='control_plane_stack',
                             metavar='<control plane stack>',
@@ -66,9 +63,11 @@ class ExportCell(command.Command):
 
         control_plane_stack = parsed_args.control_plane_stack
         cell_stack = parsed_args.cell_stack
-        cell_name = parsed_args.name
+        cell_name = control_plane_stack
+        if cell_stack:
+            cell_name = cell_stack
         output_file = parsed_args.output_file or \
-            '%s-cell-input.yaml' % cell_name
+            '%s-cell-export.yaml' % cell_name
 
         self.log.info('Running at %s with parameters %s',
                       self.now,
@@ -106,7 +105,7 @@ class ExportCell(command.Command):
         with open(output_file, 'w') as f:
             yaml.safe_dump(data, f, default_flow_style=False)
 
-        print("Cell input information exported to %s." % output_file)
+        print("Cell information exported to %s." % output_file)
 
         msg = """ \n\n
           Next steps:
@@ -123,7 +122,7 @@ class ExportCell(command.Command):
             - additional environment files used for overcloud stack
             - --stack <cellname>
             - cell role file created
-            - the exported cell input information file {output_file}
+            - the exported cell information file {output_file}
             - other specific parameter files for the cell\n
           For more details check https://docs.openstack.org/
           project-deploy-guide/tripleo-docs/latest/features/deploy_cellv2.html