Typo in client-server spec: ether -> either
@@ -192,7 +192,7 @@ requests can be handled correctly.
By default, the `Login`_ and `Registration`_ processes auto-generate a new
``device_id``. A client is also free to generate its own ``device_id`` or,
-provided the user remains the same, reuse a device: in ether case the client
+provided the user remains the same, reuse a device: in either case the client
should pass the ``device_id`` in the request body. If the client sets the
``device_id``, the server will invalidate any access token previously assigned
to that device. There is therefore at most one active access token assigned to
