Add basic readme info

README.md

@@ -12,7 +12,21 @@ Add the `LUNANODE_API_KEY` and `LUNANODE_KEY_ID` to your environment variables.
 
 ## Usage
 
-$$$AUTOGEN$$$
+See `lunanode help` screen.
+
+Available subcommands:
+
+* `billing`
+* `dns`
+* `dyn`
+* `floating` (for LunaNode's floating IP system)
+* `image`
+* `network`
+* `record` (DNS)
+* `ssh-key`
+* `vm`
+* `volume`
+* `zone`
 
 ## TODO (looking for contributors)