Sensitive detector framework

This MR includes:

• An interface class for sensitive detector plugins
• A loader to load the sensitive detector plugins.
• Enhancements to FSLDetectorConstruction class to schedule and load the S.D. plugins, using the aforementioned loader.
• CMake modifications such that client code can find_package (FullSimLight), at this stage just an interface package installing a single header file (FSLSensitiveDetectorPlugin.h).

assigned to @mbandier

approved this merge request

Hi @boudreau and @dellacqu, many thanks for this MR! In general everything looks fine to me. Let's discuss it at our meeting this afternoon and then we can merge it.

merged

mentioned in commit 09eab590

resolved all threads