Version 3.0.0-rc.18

• OpenSeadragon: shape stroke no longer missing on initial load (#348)
• Keyboard shortcuts for undo/redo now working on Win/Linux
• Touch selection is now more robust (#353)
• Corner handles now have (invisible) buffer space around them, making them easier to grab on touch devices (#355)
• When drawing a polygon in touch mode, resting the finger in place for >1.5 s is treated like a double click, and closes the polygon (#354)
• When shapes overlap, clicking a smaller shape "underneath" a larger shape will now select the smaller shape, even if the larger shape is the current selection (#356)