Fix incorrect help for 'nova flavor-create'

- like <id>, the <name> argument must also be unique
- <id> argument can be a string, integer, or UUID (not just an integer
or UUID like it currently says)

Change-Id: I8cf561bd361bc13caeb5cbceb662e1c51961f210
Closes-Bug: #1503503

novaclient/v2/shell.py

@@ -707,12 +707,12 @@ def do_flavor_show(cs, args):
 @cliutils.arg(
     'name',
     metavar='<name>',
-    help=_("Name of the new flavor."))
+    help=_("Unique name of the new flavor."))
 @cliutils.arg(
     'id',
     metavar='<id>',
-    help=_("Unique ID (integer or UUID) for the new flavor."
-           " If specifying 'auto', a UUID will be generated as ID."))
+    help=_("Unique ID of the new flavor."
+           " Specifying 'auto' will generated a UUID for the ID."))
 @cliutils.arg(
     'ram',
     metavar='<ram>',