function Entry(keys, obj, map) {
		this.keys = keys;
		this.map = map;
		this.obj = obj;
	}
@
#Crafty.HashMap.key
@comp Crafty.HashMap
@sign public Object Crafty.HashMap.key(Object obj)
@param obj - an Object that has .mbr() or _x, _y, _w and _h.
Get the rectangular region (in terms of the grid, with grid size `cellsize`), where the object may fall in. This region is determined by the object's bounding box.
The `cellsize` is 64 by default.

@see Crafty.HashMap.constructor