popup: flip above the pointer at the bottom edge

Without a caret the popup sat at pointer+10 and was clamped upward at
the bottom of the work area, covering the pointer; it now goes above the
pointer like it goes above a caret.

popup_layout.c

@@ -259,6 +259,8 @@ popupposition(Caret *caret, int pointerx, int pointery, Area *area,
 	}else{
 		px = (vlong)pointerx + 10;
 		py = (vlong)pointery + 10;
+		if(py + h > bottom)
+			py = (vlong)pointery - 10 - h;
 	}
 	xmax = max(right - w, area->x);
 	ymax = max(bottom - h, area->y);