Update app directory structure, add home and routes

atst/app.py

@@ -0,0 +1,13 @@
+import tornado.web
+from atst.handlers.main import MainHandler
+from atst.home import home
+
+def make_app(**kwargs):
+    app = tornado.web.Application([
+            (r"/", MainHandler),
+        ],
+        template_path = home.child('templates'),
+        static_path   = home.child('static'),
+        **kwargs
+    )
+    return app