Fix whitespace within wiki markup

[cgay]

If wiki markup contains a line break in the middle it can break the link. e.g.,

{{Dylan
Compilers}}

doesn't link to "Dylan Compilers". This can happen when the browser's textarea widget auto-wraps the line (which I believe can be fixed in the HTML) but also if someone is writing RST and hard-wraps the lines for readability. I think it's okay to convert all contiguous white space inside {{...}} to a single space.