Add an alias 'name=' for guest

This is the opposite as library/virt, but much better than using name= as the default option name.

vsphere_facts

@@ -84,7 +84,7 @@ def main():
             host = dict(required=True),
             login = dict(required=True),
             password = dict(required=True),
-            guest = dict(required=True),
+            guest = dict(required=True, aliases=['name']),
         )
     )