pep8 blank lines fixes

flake8 --select W391,E302,E301,E304

autopep8 can't fix W391 even though it claims it can.
Fixed using a simple custom script.

weboob/tools/log.py

@@ -59,6 +59,7 @@ class ColoredFormatter(Formatter):
     Class written by airmind:
     http://stackoverflow.com/questions/384076/how-can-i-make-the-python-logging-output-to-be-colored
     """
+
     def format(self, record):
         levelname = record.levelname
         msg = Formatter.format(self, record)