Fixed issues with repeat opcodes in the PEFRelocator
Got rid of IExecutionEngine, this wasn't going to work anyways
Got tired of calling it an "IAllocator". I never picked on the calling convention, and even if I did, it's not an interface.
Fixing warnings the right way: default constructor of BigEndianInt really should be trivial
Dummy and inimplementation of atexit. Only registers callbacks, doesn't use them. This needs executable support, will have to check how that works.
Switched to <chrono> for time manipulations