Updated README for configuration

Author: mota

README.md

@@ -6,9 +6,19 @@ API to generate millipedes
 
 ## Documentation
 
-GET /api/\<version\>/millipede
+`GET /api/\<version\>/millipede`
 * return: a millipede
 * parameters:
     * size: provide the size of the millipede (default is 10)
     * reverse: true to have a reverse millipede (default is false)
     * comment: provide a comment to the generated millipede
+
+## Configuration
+
+By default MaaS looks for an optional configuration file located to `/etc/maas.cfg`.
+You can override this value by setting the environment variable `MAAS_CONFIG_FILE` to whatever it pleases.
+
+The configuration file expected content is valid python code.
+
+### Values:
+* `REDIS_URL`: Url to the redis server for cache purpose. Caching is optional but greatly recommended