Add reference to issue #48.

[msporny]

Add reference to issue #48.

[adrianhopebailie]

@msporny Can you reword this to be a lot simpler and leave the deeper explanation for users to read in the issue itself? I would also suggest placing this issue marker alongside those for #15 and #16 which also relate to the shape of the API.

Suggestion:

<div class="issue" data-number="48" title="Should list of accepted payment methods be 
strings or objects?"> There is an open issue about whether the list of supported payment 
methods should be passed to the user agent as a simple sequence of strings or as a more 
complex and flexible object structure.</div>

[msporny]

@adrianhopebailie wrote:

Can you reword this to be a lot simpler

Done. Used your text and requested location.

[adrianba]

Merged as fcfe1d1