[#706] PEP8 Compliance

If you want me to actually remove the changes from `dht.py`, `market.py` and `transport.py` let me know.
I can also add a test for PEP8 compliance.
@yagoulas 
![touche](https://cloud.githubusercontent.com/assets/163977/5133032/97e7d386-70cf-11e4-9347-92ce4651a5b1.gif)