feat: add "web handler" feature; it must get the menu handler

this makes more sense than (potentially) adding a whole bunch of
methods to the app handler.

also fix entry point for app provider, per wj changes

tests/test_handler.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8; -*-
+
+from unittest import TestCase
+
+from wuttjamaican.conf import WuttaConfig
+
+from wuttaweb import handler as mod
+from wuttaweb.menus import MenuHandler
+
+
+class TestWebHandler(TestCase):
+
+    def setUp(self):
+        self.config = WuttaConfig()
+        self.app = self.config.get_app()
+        self.handler = mod.WebHandler(self.config)
+
+    def test_menu_handler_default(self):
+        menus = self.handler.get_menu_handler()
+        self.assertIsInstance(menus, MenuHandler)