Rectangle Model for Unit tests

RectangleModel.kt

/**
 *  o1----------------------o
 *  |                       |
 *  |                       |
 *  |                       |
 *  o-----------------------o2
 *
 *  @param topLeftPoint would be o1
 *  @param bottomleftPoint would be o2
 */

class RectangleModel constructor(
        private val topLeftPoint: Point,
        private val bottomleftPoint: Point)

class Point constructor(val x: Int,
                        val y: Int)