[json] fix json serialization for recent simplejson implementation, and test encoding of entities as with earlier simplejson implementation, iterencode internal stuff is a generated function, we can't anymore rely on the _iterencode overriding trick, so move on by stoping isinstance(Entity, dict). This is a much heavier change than expected but it was expected to be done at some point, so let's go that way.

function load_now(eltsel, holesel, reloadable) {
    var lazydiv = jQuery(eltsel);
    var hole = lazydiv.children(holesel);
    if ((hole.length == 0) && ! reloadable) {
        /* the hole is already filled */
        return;
    }
    lazydiv.loadxhtml(lazydiv.attr('cubicweb:loadurl'));
}

function trigger_load(divid) {
    jQuery('#lazy-' + divid).trigger('load_' + divid);
}