Add fake traps, improve MachineMemory, fix RTI condition (RTI still not implemented)

    IN, GETC, OUT, PUTSP, PUTS, and HALT are all done in C++
    MachineMemory throws an exception if access would be out of bounds
    MachineMemory allows for access to BYTE array
    Renamed MachineMemory::_mem to MachineMemory::rawmem