Added AGEEvent class. This will be the base class for GEEvent containing all of the GEEvent traits as well as one of the base classes for COINCEvent. While not really an abstract class, this will simplify the COINCEvent class (the class itself and how it copies the GEEvent/LYSOEvent data). Organizationally, the goal is to separate the parsing and the analysis portions of processing. Parsing will ONLY get the raw data out of the data files. Separately, analysis will create branches/trees of calculated values; this makes it so parsing only needs to be done ONCE (saving time from not having to do the same calculations over and over). This also means less changes to the GEEvent/LYSOEvent classes (which forced re-parsing) since the analysis functions will be separate. Trees with analysis calculations can easily be deleted (or added to) if improvements are made in the analysis code instead of re-parsing the whole file. ALYSOEvent will also be added in the same vein.