[rset] add test for #1251252, actually fixed in rql; fix docstring and add comments in rset.related_entity to make things clearer
/*
* 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;
}