Allow custom profiler.js path, which makes jQuery dependency optional.

Use case: Due to the non-sandboxed nature of JS in the browser, and the fact that everyone does not use jQuery, it may not be desirable to load (one or more) jQuery libraries into the window object for the purposes of the profiler. I propose we allow a custom profiler.js path via app config, to give front-end devs the option to override the profiler JS with their own.