Support custom auth URLs in stf local and map oauth2 to the correct URL by default.

lib/cli.js

@@ -826,6 +826,9 @@ program
     , 'auth type'
     , String
     , 'mock')
+  .option('-a, --auth-url <url>'
+    , 'URL to auth client'
+    , String)
   .option('--auth-port <port>'
     , 'auth port'
     , Number
@@ -965,11 +968,11 @@ program
             'app'
           , '--port', options.appPort
           , '--secret', options.authSecret
-          , '--auth-url', util.format(
+          , '--auth-url', options.authUrl || util.format(
               'http://%s:%d/auth/%s/'
             , options.publicIp
             , options.poorxyPort
-            , options.authType
+            , ({oauth2: 'oauth'}[options.authType]) || options.authType
             )
           , '--websocket-url', util.format(
               'http://%s:%d/'