[Minor] Usability: Increase transition for opacity change of non-CU-page overlay
[Fix] Fix occasional error in positioning of non-CU-page-overlays
[Feature] Allow longer transition for when removing/applying "non-CU-dimming" on scroll pause compared to when the user changes the dimming using +/- keys
[Feature] Calling changeSpotlightOnSelecteCU() selects the most sensible CU, if none is selected
[Minor] Don't need to specify "px" with "0"
[Fix] Fix issue where we try to directly set window.pageYOffset or window.pageXOffset (since these can't be set directly)

 - Issue which was introduced by a recent commit where we replaced body.scrollTop (and body.scrollLeft) with window.pageYOffset (and window.pageXOffset) for better reliability/cross-browser-compatibility (and since body.scrollTop (and body.scrollLeft) seemed to be getting deprecated)
[Fix] When 'Esc' is pressed with the focus on filtering-UI-text-box, suppress the event after closing the filtering-UI
[Fix] Restore both x and y scroll coordinates after change focus
[Feature/Fix] The option animatedCUScroll (and other related options) is being called animatedScroll and now affects both CU scroll and regular page scroll etc.

 - Also fixes #212
 - mod_CUsMgr: minor fix where document.scrollLeft (which was erroneously used instead of document.body.scrollLeft) has been replaced with window.pageXOffset