code: function(jid) {
          var s = jid.split('/');
          if (s.length < 2) return null;
          s.splice(0, 1);
          return parseInt(s.join('/'));
      }
docs: Get user id from dialog's full jid.
  @memberof QB.chat.helpers
  @param {String} jid - dialog's full jid.
  @returns {String} user_id - User Id.