bottle ujson optional dependency (#2947)

* ujson dependency

increment speed for json response
https://github.com/bottlepy/bottle/blob/master/bottle.py#L82
https://github.com/bottlepy/bottle/pull/933

* performance json response

frameworks/Python/bottle/requirements-pypy.txt

@@ -4,3 +4,4 @@ SQLAlchemy==1.0.12
 gunicorn==19.4.5
 PyMySQL==0.7.2
 tornado==4.3
+ujson==1.35

frameworks/Python/bottle/requirements.txt

@@ -6,3 +6,4 @@ meinheld==0.6.1
 mysqlclient==1.3.7
 greenlet==0.4.9
 uwsgi==2.0.12
+ujson==1.35