Tweaked Cursor and Dragging Mode Behaviour

[ryanpmcguire]

• UpDownLeftRight resize cursor appears when moving over mouse, boosting click accuracy and reducing frustration immensely.
• DraggingHandCursor now appears when drag/panning, regardless of whether you are moused over a note
• One can now drag/pan even when starting on a note
• Note tuning now requires middle click + drag instead of just middle click

[ryanpmcguire]

This commit accidentally included the wrong RollBase.cpp file. I will update this request with the correct file in a few hours.