Fire touch event for when a touch enters a UI element

[yaustar]

There are use cases where we would want to know if a touch is moved onto an element such moving between on screen buttons for a dpad

Forum discussion: https://forum.playcanvas.com/t/touch-enter-event/25294

[wadim-al]

I'm also interested in touchleave event for the same purpose: dpad

[eproasim]

Going to add my own interest to this one. The current application that I'm working on requires the user to drag elements over top other elements (not in a grid) to check if a match has been made.