SF patch #470393 (Jim Ahlstrom): Add missing marshal function

In Include/, marshal.h declares both
    PyMarshal_ReadLongFromFile()
    and PyMarshal_ReadShortFromFile(),
    but the second is missing from marshal.c.

[Shouldn't the return type be declared as 'short' instead of 'int'?
But 'int' is what was in marshal.h all those years...  --Guido]