add bottle simple_server using gunicorn

tests/performance/bottle/simple_server.py

@@ -0,0 +1,10 @@
+from bottle import route, run
+import ujson
+
+
+@route('/')
+def index():
+    return ujson.dumps({'test': True})
+
+
+run(server='gunicorn', host='0.0.0.0', port=8080)