[entity] more tweaks for entity attribute cache handling on cw_set/cw_create to fix test regression * when an attribute is listed in dont-cache-attrs, purge any previous value * test value is actually modified in EditedEntity.__setitem__ before adding attribute to dont-cache-attrs

/*
 * cubicweb js mock for unit tests
 * This module defines variables and functions used in quite a few places
 * in cw js framework that can't be used or guessed without a real CW server
 */

var pageid = 'my-page-id';

function _(message) {
    return message;
}