Revised freeboard module from PIAS

Although the freeboard calculation module of PIAS is not core of the suite, it is still intensively used in many phases of the ship design process. For that reason we have taken up this module — from which the origin lies 20 years back — and brought it in line with the look and feel of the other PIAS modules. One enhancement is that hullform parameters can now directly be derived from PIAS’ hull model. The applied algorithms remains unchanged, so computation results will not be affected.