Enable pylint, black and flake8 in tox.ini

Change-Id: I5e252eb4802b79497a3fdfea63488668d8a8c692
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/osm_nbi/engine.py b/osm_nbi/engine.py
index 37f1fb2..e9b1549 100644
--- a/osm_nbi/engine.py
+++ b/osm_nbi/engine.py
@@ -293,7 +293,9 @@
         :return: The list, it can be empty if no one match the filter_q.
         """
         if topic not in self.map_topic:
-            raise EngineException("Unknown topic {}!!!".format(topic), HTTPStatus.INTERNAL_SERVER_ERROR)
+            raise EngineException(
+                "Unknown topic {}!!!".format(topic), HTTPStatus.INTERNAL_SERVER_ERROR
+            )
         return self.map_topic[topic].list(session, filter_q, api_req)
 
     def get_item(self, session, topic, _id, filter_q=None, api_req=False):
@@ -307,7 +309,9 @@
         :return: dictionary, raise exception if not found.
         """
         if topic not in self.map_topic:
-            raise EngineException("Unknown topic {}!!!".format(topic), HTTPStatus.INTERNAL_SERVER_ERROR)
+            raise EngineException(
+                "Unknown topic {}!!!".format(topic), HTTPStatus.INTERNAL_SERVER_ERROR
+            )
         return self.map_topic[topic].show(session, _id, filter_q, api_req)
 
     def get_file(self, session, topic, _id, path=None, accept_header=None):