Implement Joomla 3 preload feature for Akeeba Strapper

Here you go Nicholas, thanks a LOT for accepting such a feature! Did you also had something like this in mind? I thought about adding more control for the preload feature (what to preload: CSS, JS, LESS, jQuery, jQuery UI), but this gets quite complicated. I think KISS should do the job.

I implemented the following check, which could perhaps also better be implemented for Joomla 2.5:
<pre>// Do not allow Joomla! 3+ preloading if jQueryLoad is "auto" or "namespace" (which are both
// namespace in Joomla! 3+). Else only the namespacing for the jQuery library will be loaded,
// without a jQuery library being loaded on forehand, which results in jQuery error(s).</pre>

Cheers :)
Jurian