update readme with new configuration options

README

@@ -10,10 +10,20 @@ the specified port you should get a JSON response containing the current node in
 
     Configuration options:
             --no-daemonize               Don't daemonize the web server process
-        -p, --port PORT                  The port to run web-puppet on
-
-    Common options:
-        -h, --help                       Display this screen
+        -p, --port PORT                  The port to run web-facter on
+        -c, --config FILE                The file to load with configuration options
+        -h, --help                       Display this screenp
 
 Note that in most setups the yaml directory containing the node information isn't readable
 by all users, so you may need to run this as puppet or root.
+
+You can configure web-puppet using a configuration file, using the following format, and
+specifying the filename with the --config option above.
+
+    username=gilbert
+    password=george
+    port=3009
+    daemonize=true
+
+Note that the port and daemonize options will override those on the command line.
+The username and password options enable HTTP basic authentication using those details.