c dez port

I had a couple of hours to burn Sunday morning so I ported over the rest of the dez code to C, although I didn't feel like testing it till I had some hours to burn today.

Anyway, I fixed some bugs and ran some tests. It's only about 30-50% faster than the Java version on the bible test for practical "limit" values. The patches generated aren't necessarily identical because of some minor changes in the hash table design but the differences are minor. The C code also requires some more bounds and error checking for robustness.

I also added CRC32 checksums to the file format as a quick check that the input and output aren't corrupted.