NAME
       LoadFile -- load a source code file into memory

   SYNOPSIS
       filePtr = LoadFile(fileName);
       D0                 A0

       struct BlitzFile * filePtr = LoadFile(char * fileName);

   FUNCTION
       This function will load a file into memory. Memory required to store the
       file is allocated by this function. This function can read ASCII files
       as well as the standard Blitz tokenised source files. Tokenisation is
       performed if required.

   INPUTS
       fileName - a pointer to a null-terminated string holding the name of the
                  file to load

   RESULT
       filePtr - a pointer to a BlitzFile structure (or NULL for failure)