Merge branch 'master' into struttura

managetests.json

+{
+    "build": [
+        ["invoke", "build"]
+    ],
+    "before_install": [
+        ["mkdir", "{{base}}/data"],
+        ["virtualenv", "-p", "python3", "{{base}}/env"]
+    ],
+    "install": [
+        {
+            "artifacts": "build/packages/*.whl",
+            "command": ["{{base}}/env/bin/pip", "install", "{{artifact}}"]
+        }
+    ],
+    "run": [
+        "{{base}}/env/bin/uitwww", "run", "-g", "{{gunicorn_config_file}}",
+        "{{base}}/data"
+    ]
+}

uitwww/__init__.py

@@ -35,7 +35,7 @@ def create_app(data_path):
 
     @app.errorhandler(404)
     def not_found(error):
-        return flask.render_template("404.html")
+        return flask.render_template("404.html"), 404
 
     return app