We now require PuppetDB 1.5 / API v3.

PUPPETDB_API is no longer configurable since we're now using features
that are v3 only. Limiting ourselves to v2 compatibility is far too
troublesome and people tend to update to newer versions of PuppetDB
fairly quickly.

puppetboard/app.py

@@ -27,7 +27,7 @@ app.config.from_envvar('PUPPETBOARD_SETTINGS', silent=True)
 app.secret_key = os.urandom(24)
 
 puppetdb = connect(
-        api_version=app.config['PUPPETDB_API'],
+        api_version=3,
         host=app.config['PUPPETDB_HOST'],
         port=app.config['PUPPETDB_PORT'],
         ssl=app.config['PUPPETDB_SSL'],