v2.0.0

This version replaces the use of vector variable_name to vector variable_name
With MyClass set to handle the list of gamma-ray transitions (MyTransition), levels (MyLevels) and gamma-gamma coincidences (gammagamma)

This allows the functions which use these vectors to be understood more easily as it should be clear what the elements of the variables are.
This also means the adding new or changing elements to the Class is easier.

Additionally the FindCoincidences() function in SimulateCoincidences.cc has been updated to use recursion rather than multiple nested loops which required editing if the input data was especially large.

There is the introduction of classes for triple-gamma-coincidences. This feature requires further testing before it will be included.