Merge pull request #61 from CrepeGoat/fix/59-filter-deprecation-errors

changed `on_stderr` to filter deprecation errors

Author: kaste

linter.py

@@ -27,6 +27,7 @@ def on_stderr(self, stderr):
         stderr = re.sub(
             'No config file found, using default configuration\n', '', stderr)
         stderr = re.sub('Using config file .+\n', '', stderr)
+        stderr = re.sub('(?m)^.*DeprecationWarning.*\n.*\n', '', stderr)
 
         if stderr:
             self.notify_failure()