Draw2D touch version 5.7.1 released

+ fixing broke resize of SetFigure (e.g. Icons).
+ source and target decoration of an connection isn't handle correct with the toFront and toBack operation - fixed.
+ fix broken serialization of "Line" if the vertices in the JSON document contains less than 2 vertex. This will break the complete reading of the document.
+ fixing wrong icon size of collapsible figure
+ respect the "visible" flag of a child by calling the method "add"
+ fixing wrong width calculation of verticalLayout
+ fixing that ports are not moved when a figure is moved.