Add BeforeRequestCallback and public getter/setter for ClassPrefix/BeforeRequestCallback

[yberkholz]

Add feature BeforeRequestCallback

Add public getter/setter for properties

• ClassPrefix
• BeforeRequestCallback

Offers the possibility to change the classprefix and modify the XHR request, e.g.:

hinclude.setClassPrefix('hinclude-http-error hinlcude-http-');

hinclude.setBeforeRequestCallback(function(req, url) {
    req.setRequestHeader("X-Requested-With", "XMLHttpRequest");
    req.setRequestHeader("X-Request-Source", "HTMLInclude");
});

[mnot]

If you rebase and add some tests (see the tests directory), I'll take the pull request. Sorry for the delay -- wanted to get the test infrastructure in place.

[kingcrunch]

/ping @yberkholz

This would solve #24 too: With this PR everybody could decide themself, if they send this with or without X-Request-With (as mentioned in this comment).

[L0rD59]

Up ?