[added] GLM math / vector / matrix / random functions
[added] Time in Millis to GameClock
[added] Various utility imports to AreteEngineStd.hpp
[added] GenericObjectFactory for future use with uncompleted features
[changed] Moved Enums and Structs from Types to Structs
[changed] Moved ISingleton to Templates
[changed] ISingleton constructor to protected added a CreateInstance method which returns a shared_ptr of the derived type - this is to allow the classes to not be used as singletons
[changed] Classes which inherit singleton to use the new CreateInstance instead of make_shared
[removed] IEventManager interface, unneccessary with refactored class scope