Defining scattered photons

[ckarwin]

Currently, the code defines a scattered photon if the measured incident angle varies from the the initial incident angle. This is done with the binned response, and so the resolution is limited by the angular bin size (4 degrees in the main paper). In the latest release of the code, I now implemented a way to track all photon interactions. It is now very easy to identify which photons scattered based on the event sequence, which is stored as a string. However, this requires storing all interaction information in the simulation file, which results in a larger file size.

An option should be added to determine the scattered component based on the interaction sequence string of the photon. Whether or not this becomes the default behavior needs to be determined.