Three unsigned integers is overkill for handling dates.
Implements #65: Date structure can be represented with a single 32bit
value
Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>
I don't think it makes sense that callers of file_open() are expected to
check the file version after opening. This should be something handled
by the file code so we can print a consistent error message.
Implements issue #5: Better file versioning
Signed-off-by: Anna Schumaker <Anna@OcarinaProject.net>