Add documentation on auth

doc/api/tokenauth.rst

@@ -0,0 +1,36 @@
+.. _`rest-tokenauth`:
+
+Token-based authentication
+==========================
+
+Obtaining an API token
+----------------------
+
+To authenticate your API requests with Tokens, you need to obtain a team-level API token.
+You can create a token in the pretix web interface on the level of organizer teams. Create
+a new team or choose an existing team that has the level of permissions the token should
+have and create a new token using the form below the list of team members:
+
+.. image:: img/token_form.png
+   :class: screenshot
+
+You can enter a description for the token to distinguish from other tokens later on.
+Once you click "Add", you will be provided with an API token in the success message.
+Copy this token, as you won't be able to retrieve it again.
+
+.. image:: img/token_success.png
+   :class: screenshot
+
+Using an API token
+------------------
+
+You need to include the API token with every request to pretix' API in the ``Authorization`` header
+like the following:
+
+.. sourcecode:: http
+   :emphasize-lines: 3
+
+   GET /api/v1/organizers/ HTTP/1.1
+   Host: pretix.eu
+   Authorization: Token e1l6gq2ye72thbwkacj7jbri7a7tvxe614ojv8ybureain92ocub46t5gab5966k
+