add dummy mutr station 1

A suggestion from Pat: add a dummy plane to the SVX which is located at MuTr station 1. This allows a selection on tracht that make it through the absorber into the MuTr volume.

In magenta are shown the SVX detector, plus the dummy silicon planes in the locations of the MuTr stations 1.

The planes are placed at +-190 cm, and are PCON's with inner radius 30 cm, outer radius 140 cm.

cfm_sngp
ptrig 1
exec show1.kumac
dxyz
dhits

This is a front view of North station 1 plus the dummy plane.

How to use:

Use the phnx.par file named phnxSili_19aug05.par, and turn the planes on with this line:
```
station1_dummy = 1,
```
In the pisa.kumac file, turn the MUTR off, otherwise you have conflicting volumes in Geant:
```
MUM  'ON' 'FULL' 'ETOT' 'FULL' 'MCAL' 0. 0. 0. 'STCK' 'NNEU'  ! Muon trackers
```

SVX source file: svx_19aug05.f

Last update 22 Aug 2005