Full implementation of the twisted trapezoid shape
This merge request introduces a new shape in GeoModel: GeoTwistedTrap that is based on G4TwistedTrap shape. Correspondingly GDMLtoGM is updated with a handler for GeoTwistedTrap, and GeoModel2G4 can recognise the GeoTwistedTrap and create a G4TwistedTrap from it. Persistification of this shape is implemented in GeoModelRead and GeoModelWrite and DumpShape of GMEX. The visualisation in GMEX of the twisted trapezoid is handled by SbPolyhedrizeAction, SoVisualizeAction and SbPolyhedron classes. In particular some new classes have been introduced (SbTwistSurface, SbTwistTrapParallelSide, SbTwistTrapAlphaSide and SbTwistTrapFlatSide) for a better rendering of the twisted trapezoid within gmex.
It solves issue #8 (closed)
Edited by Marilena Bandieramonte