Add Logging to OOInteraction
Fix many bugs in parsing by enhancing the overall mechanism
Allow operator tokens of more than 2 symbols, e.g. @@@@@
Make it easier to adjust the signature of compound expressions
Add a test to parse all possible combination of tokens up to a length
Fix an incorrect assertion when parsing expressions
Improve the expression parsing tests
Clean NodeWrapper up a bit
Make Item::synchronizeCollections static

Allows for situations where the synchronized items have no parent
Add initial code for overlay infrastructure and use it for selections
Remove the now obsolete Highlight concept (Overlays took over)
Move and rename the old selection item to overlays/SelectionOverlay
Correctly update the cursor's size and position on each scene update
Decouple OverlayGroup from the type hierarchy of the Overlay Items
Change Overlay to be a template mix-in like class
Change some names in Overlay to avoid name collisions
Initial implementation, still needs control for when to show labels
Add a translucent white background for zoom labels
Scale zoom labels to fit within their associated item
Do not show a zoom label for RootItem