PEP8 cleanup for node/market.py through node/openbazaar.py

Minor PEP8 clean up commit 2 of 3.
Maybe break this up into 2 `print` statemens:
```python
print "Warning: UPnP was not setup correctly.",  # notice the `,` that  makes python stay on the same line
print "Ports could not be automatically mapped."
```