Commented out broken detector classes.
Added inteface DetectorLayerFactory and modified DetectorLayer, AbstractDetectorGeometry, and AbstractDetectorLayer to make the implementation of a specific Detector a matter of implementing an appropriate DetectorLayerFactory.
Added a method to generate whole detectors in the DetectorLayerFactory and implmented classes for the ECDetector (PCAL only).
Updated .gitignore to ignore nbproject/private/