Disabled the 'mapParams' option of restify's bodyParser plugin so that the parsed data from a URL-encoded POST body is assigned to the body property and not params. Fixes the feedback form and any other POST endpoints that were expecting a parsed object from a URL-encoded body.
Reverted change to 'mapParams' option, and instead replaced all uses of the 'body' field with 'params', since the bodyParser plugin maps the parsed body data to 'params'. This also means we can be consistent with data access for both GET and POST / PUT requests.
Merge pull request #164 from cvan/body-parsing-fix

Fixed parsing of requests with a URL-encoded body