Fix comments and unittest for market.py and style

Trying to make the right commit to  the develop branch.
The indentation is misleading as it makes the expressions below look like arguments to `new_peer.send` while they are arguments to `proto_page`. Please restyle like [this](https://github.com/OpenBazaar/OpenBazaar/pull/658/files#diff-06caaf3cbf31ee2085d6189a8fe7e166R478)