TabPane:    Second attempt at fixing the scrolling bar issue (i.e. adjustClipping). This is complete, but rather slow, because we recompute the submorphs bounds every time, because the cachedBounds don't include submorph bounds when clipping.
HistoryTracking:
activated history tracking and browsing for the SCB by default
MethodFinderPane:
removed the toolingPatches, to prevent .openPartItem to modify any loaded PartsBin/Dialogs/MethodFinderPane,
resolved feature request from issue #200
ListMorph:
fixed issue #173 by removing unused listelements from the listcontainer