OARIS — No identity_type field on the sensor_track_type class

It is inconsistent to define an identity_type field for use with system_track_type class but to then not have the option to use it with the sensor_track_type class.

Add an identity attribute to sensor_track_type

Add an optional sensor_track_pre_identification attribute with type identity_type to sensor_track_type. This is the sensor's view of the tracked object's identity for cases where a sensor has such a capability.