Draw2D touch version 4.7.2 released

+ fixing Polygon.setPosition. The method didn't care about the generic parameter behaviour. "x" can be a number or a draw2d.geo.Point
+ new method draw2d.geo.Rectangle#contains. Return true if the this rectangle contains the hand over rectangle.
+ new parent class for Composite figures.
+ new method Figure.toBack
+ fixing the behavior of the Raft shape. Care about enveloping rafts and z-index of the figures.