Massive commit to flesh out the geometry in more details.

Massive commit to flesh out the geometry in more details.
Most of the geometry is there.  Missing - if at all relevant are only

- Cooling pipes in FMD3
- Cooling fin in FMD2

Although all volumes are there, it should be noted that the
geometry should really be checked against CAD drawings and
installation/assembly notes.  This will, however, take some
time to do, and I need some information from the relevant
parties.

What has been added to the geometry is

- Support of FMD2 - barrel, covers, and flanges.
- Support of FMD1 - both the upper and lower saucers are there.
- Digitiser cards on all half-rings.
- Cooling plates on FMD3

What has been changed in the geometry is

- Sensors are now put into an assembly together with the hybrid
  cards and the stand-offs.  This is to make it easier to have
  enough clearance for alignment, and it is, after all, more likely
  that the mounting of a module (sensor+hybrid+stand-offs) to the
  honeycomb plates is less precise than the compound itself.
- The cone of FMD3 is now made as a composite shape of a cone minus
  the openings where the cooling plates sit.
- Computations done more robust - gone are a lot of stupid fudge
  parameters.

Other changes are for the display and alignement macros and similar.