fix(referencebrowser): just remove it

Add an referencebrowser.js in the skin directory to take precedence
on the official one and remove the overlay statement which
make JS fails because we don't want jquerytools on mobile.

We seriously need a content picker for mobile.
fix(archetypes widget file): widget javascript handle ui-disabled

jquerymobile wrap inputs so when an input is disabled the wrapper
got a ui-disabled class. The archetypes file widget does not
handle this, so you can't modify a file field of an archetype
object.

The onlclik event has been changed to use jquery this way:
$('#${fieldName}_file').prop('disabled', true)
.parent().addClass('ui-disabled');