Util methods for registrate service

[muuki88]

Create a util class or methods in AbstractSensor for easy registration.

String[] driverClasses = new String[] { ISensorDriver.class.getName(), Driver.class.getName() };
String[] sensorClasses = new String[] { ISensor.class.getName(), Device.class.getName() };

ISensor sensor = new MySensor();
Dictionary<String, Object> sensorProps = new Hashtable<>();
sensorProps.put(Constants.DEVICE_CATEGORY, sensor.getCategory());
sensorProps.put(Constants.DEVICE_DESCRIPTION, sensor.getDescription());