minor fixes;
- DESCANT and SCEPTAR were using the channel number as detector number instead of the mnemonic
- activated DESCANT waveforms as default
- grsisort tried to access the first root-file whether any root-file was provided or not
- added gamma-gamma matrices to MakeMatrices that use addback if the angle between the detectors is less than 90 degree (this is probably specific to the 32Na experiment)