Add pep8 config, use pep8 in travis

also, fix E111-E113 errors:
E111 - indentation is not a multiple of four
E112 - expected an indented block
E113 - unexpected indentation

>>     I'm proposing to use 1.5.6, and stick with it until we decide that some
>>     future revision of pep8.py fits our needs better.
>
> Can you explain why?
>
> It has same issue

Ah okay, I thought it wouldn't.
Let me nail it down: "whatever version gives us the checking that we 
want". Could be some even earlier version, could be the current git version.
My point being, I'd like to stick with some known good version of 
pep8.py, so we don't get hit by regressions in it.