Error handling in the library :)

[fgimian]

Hey Vladimir,

Great job on this library, it parses my UDF ISOs perfectly.

I notice at the moment that the code has quite a lot of panics instead of returning errors when things go wrong. As such, the library panics if an invalid file is read with it.

Would you consider adding some error handling to your library so it is more robust?

Thanks so much!
Fotis