Use a separated option '--env-name' to render a new environment

Change-Id: I3bfa9dc52f141d0d5ab5d372eea63799eacb12ab
diff --git a/reclass_tools/cli.py b/reclass_tools/cli.py
index c696400..864ba7b 100644
--- a/reclass_tools/cli.py
+++ b/reclass_tools/cli.py
@@ -109,7 +109,8 @@
 
         create_inventory.render_dir(template_dir=self.params.template_dir,
                                     output_dir=self.params.output_dir,
-                                    contexts=self.params.contexts)
+                                    contexts=self.params.contexts,
+                                    env_name=self.params.env_name)
 
     def get_params(self):
 
@@ -140,6 +141,11 @@
             help=('Show only the nodes which names are ended with the '
                   'specified domain, for example: example.local'))
 
+        env_name_parser = argparse.ArgumentParser(add_help=False)
+        env_name_parser.add_argument(
+            '--env-name', '-e', dest='env_name',
+            help=("Name of the 'environment' to create or use"))
+
         vcp_only_parser = argparse.ArgumentParser(add_help=False)
         vcp_only_parser.add_argument(
             '--vcp-only', dest='vcp_only',
@@ -210,7 +216,7 @@
                                     "node for already generated inventory "
                                     "only!"))
         subparsers.add_parser('render',
-                              parents=[render_parser],
+                              parents=[render_parser, env_name_parser],
                               help=("Render cookiecutter template using "
                                     "multiple metadata sources"))