Update ahdc geometry

[ftouchte]

The current geometry in coatjava is very old and slightly differs from the final design of the detector.

• The end points are in z=-188 mm and z=+162.5 mm instead of ±150 mm
• The stereo angles are not exactly 20° but : 19.1489°, 19.2857°, 20.0°, 20.6897°, 20.0° respectively for each super layer.

As the length of the wires are bigger, we reduce the sensitive volume of the AHDC cell to prevent overlaps with other part of the detector.

Corresponding PR in coatjava: JeffersonLab/coatjava#1089

[ftouchte]

@maureeungaro do you know how I could fix these errors?

[maureeungaro]

I'm working on micromegas geometry, the errors will be fixed once it's completed.