function Point(x, y) {
	    this.x = x;
	    this.y = y;
	}
A standalone point geometry with useful accessor, comparison, and
modification methods.

@class Point
@param {Number} x the x-coordinate. this could be longitude or screen
pixels, or any other sort of unit.
@param {Number} y the y-coordinate. this could be latitude or screen
pixels, or any other sort of unit.
@example
var point = new Point(-77, 38);