Use default flake8 config
diff --git a/pre_commit_hooks/trailing_whitespace_fixer.py b/pre_commit_hooks/trailing_whitespace_fixer.py
index 4fe7975..b2b6418 100644
--- a/pre_commit_hooks/trailing_whitespace_fixer.py
+++ b/pre_commit_hooks/trailing_whitespace_fixer.py
@@ -60,12 +60,12 @@
     if '' in md_args:
         parser.error('--markdown-linebreak-ext requires a non-empty argument')
     all_markdown = '*' in md_args
-    # normalize all extensions; split at ',', lowercase, and force 1 leading '.'
+    # normalize extensions; split at ',', lowercase, and force 1 leading '.'
     md_exts = [
         '.' + x.lower().lstrip('.') for x in ','.join(md_args).split(',')
     ]
 
-    # reject probable "eaten" filename as extension (skip leading '.' with [1:])
+    # reject probable "eaten" filename as extension: skip leading '.' with [1:]
     for ext in md_exts:
         if any(c in ext[1:] for c in r'./\:'):
             parser.error(