add Reader and Writer

Hi,

I've implemented a Reader and a Writer, hope this can be used!

Now the ecc bytes are written at the end of each block, thus the ecc bytes are interleaved with the original data bytes. I've only a vague idea what shall be a multi-level Reed-Solomon coding to achieve more safety even for erasure of whole 4096 byte blocks...
Can you give me some pointers?
(My vague idea is to write the first level ecc bytes to a buffer and whenever this buffer reaches the 255 byte threshold, then write out a "meta" ecc block for these - this could be a second level ecc. But this would make the reading more complex, imho)

Thanks,
Tamás Gulácsi