feat: add basic "create order" feature, docs, tests

just the package API docs so far, narrative will come later

tests/web/test_menus.py

@@ -0,0 +1,12 @@
+# -*- coding: utf-8; -*-
+
+from sideshow.testing import WebTestCase
+from sideshow.web import menus as mod
+
+
+class TestSideshowMenuHandler(WebTestCase):
+
+    def test_make_menus(self):
+        handler = mod.SideshowMenuHandler(self.config)
+        menus = handler.make_menus(self.request)
+        self.assertEqual(len(menus), 4)