You'll also need a ~/.dnsmigration.rc file of this form:
+ secret_access_key = ...
The only command line option is -r or --remove. That removes ALL records
-and zones from your route53 account. Be careful with that.
+and zones from your route53 account and does not migrate any records from
+gratisdns. It's intended to clear out your route53 account while you're
+performing practice runs. Be careful with that!