escape angle brackets in response header

Not sure about what happend to the files in `dist`, that looks a bit weird for such a small change, but i follow the steps in the readme, did `npm install` and `npm run-script build` and that is what came out :|

I realized the problem, after adding an `Link`-Header like described in [RFC5988](http://tools.ietf.org/html/rfc5988#section-5.5), which then looks like:

    Date: Mon, 17 Jun 2013 17:59:54 GMT
    Content-Encoding: gzip
    Transfer-Encoding: chunked
    Content-Type: application/json
    Link: <https://api.project.tld/transactions?page=2>; rel="next"

Since the `showStatus` method in `OperationView.coffee` just puts the response headers between `<pre>` Tags, the Link is actually treated as an unknown html-tag and not displayed in the browser.

i saw there were several escape functions in the code .. but some where hidden inside the handlebar code, others did to much in case of escaping so i used two simple `replace` calls instead.

so, having said that .. let me know what you think about it :)