v1.28.2

-- Backed out first step change to allow child GUIs to disable/enable synchronized browsing of data tree with MainGUI. It is not a good approach to change the currElem in datatree works and will needlessly overcomplicate things. Will revisit this feature in next commit with simpler approach that dos not involve major change to currElem mechanism, but rather ewach GUI will be responsible for creating it's own copy of currElem and this code will be generilized in a single utility so it can be eaily reused by any GUI.