- Before, some returned bool, and others returned int (which was then turned
into a bool with a comparison); now, everything returns a bool
- Before, some set hashes_done to nonce - 1 when a share was found and others
set it to nonce + 1 or 2. This caused some algorithms to scan/submit shares
twice with the new cpu_scanhash function. Now, it has all been replaced with
last_nonce, which is set to the final nonce checked by the scanhash_* func.
- VIA needs the full data, and cannot use midstate. All the others were
expecting midstate and data+64 for their parameters. Now, we pass midstate
and the full data pointer, and let the scanhash_* function choose which to
use.
