Improve linting setup

Author: linuxdaemon

.mypy.ini

@@ -54,6 +54,14 @@ repos:
     entry: mypy
     language: system
     types: [python]
+  - id: darker
+    name: darker
+    entry: darker
+    args:
+    - -r
+    - ':PRE-COMMIT:'
+    language: system
+    types: [python]
   - id: pylint
     name: pylint
     entry: pylint