Fix an invalid memory read bug that only recently became a problem due to the change that accepts files on the command-line. Basically, the logic would read memory beyond the end of the command line when a "-L" was given, but it would ignore all of the input until it found a NUL. After my last change, FMSLogo no longer ignored this memory, so it became more obvious that something bad was happening. I suppose this could explain some strange behavior whenever the -L parameter was given, but I have never seen any problems that I would blame on this bug.
