Fitting a UI in

Basically spent today planning up and incorporating a way to get the UI to fit in comfortably, as well as fixing several gameplay bugs, like being able to drag around invisible pointers and stacking every pointer on one space (issues caused by not ever disabling invisible pointers).

I've tweaked the zoom in various ways, such as the time it takes to zoom out, the way it picks the max scaling size (based on the largest direction - horizontal or vertical) and importantly increased the bottom portion of the screen's zoom border so that the UI won't interfere too much with anything over it.

The signals also no longer just disappear, but fade out once they reach the zoom border, so that looks pretty cool too.