Added explicit contentType and processData to the $.ajax call

Added explicit contentType and processData to the $.ajax call, so it doesn't interfere with $.ajaxSetup

At the moment, having:
contentType: "application/json",
processData: false
in the $.ajaxSetup of your application interferes with the MiniProfiler ajax calls, making the MiniProfiler not show up.

Setting these parameters explicit fixes this problem.