auth moved to docs

docs/README.md

@@ -5,3 +5,11 @@ Welcome to the documentation for Photowall API 2.
 ## Resources
 
 * [Prices](prices.md)
+
+## Authentication
+
+Authentication to the API is performed via HTTP Basic Auth. The user should provide her API key as the basic auth username parameter. An example request in cURL looks like this (adding a colon after the username prevents cURL from asking for a password):
+```
+$ curl http://localhost:5000/designers/ -u mykey:
+```
+API keys should be added to the `API_KEYS` configuration option