Enable Superset StatsD logging (#53)

As I just documented here:
https://github.com/apache/incubator-superset/pull/3813/files

👀 @hughhhh @amalakar

superset_config.py

@@ -1,8 +1,13 @@
 """Config file for Superset"""
 import os
+
 from flask_appbuilder.security.manager import AUTH_OAUTH
 from flask_appbuilder.security.sqla.manager import SecurityManager
 
+from superset import StatsDLogger
+
+ENV = os.getenv("APPLICATION_ENV")
+
 ROW_LIMIT = 5000
 SUPERSET_WORKERS = 4
 
@@ -14,13 +19,16 @@
 # superset metadata (slices, connections, tables, dashboards, ...).
 # Note that the connection information to connect to the datasources
 # you want to explore are managed directly in the web UI
-if os.getenv("APPLICATION_ENV") in ('production', 'staging'):
+if ENV in ('production', 'staging'):
     SQLALCHEMY_DATABASE_URI = 'mysql://{user}:{password}@{host}:5432/{database}'.format(
         user=os.getenv("CREDENTIALS_SUPERSET_USERNAME"),
         password=os.getenv("CREDENTIALS_SUPERSET_PASSWORD"),
         host=os.getenv("CREDENTIALS_INCENTIVES_HOST"),
         database=os.getenv("CREDENTIALS_SUPERSET_DATABASE"))
 
+STATS_LOGGER = StatsdStatsLogger(
+    host='localhost', port=8125, prefix='superset_' + ENV)
+
 # Flask-WTF flag for CSRF
 CSRF_ENABLED = True