style: fix whitespaces
style: use triple quotes for docstrings
style: fix camelCase variable names

Conflicts:

	kafka/util.py
style: fix camelCase variable names once more
style: remove extra brackets
style: remove extra brackets one more time
style: fix camelCase variable names again
don't forget to call superclass __init__
use NotImplementedError instead of NotImplementedError
remove unused exception instance variables