README: remove partial option list

The HOWTO or man page should be used, since either of those
has the full list of option keywords.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge missing content to man page

We missed the two CPU engine private options.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge in zipf differences from gfio

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge in crc32c-intel probe

Then we can kill the option callback.

Signed-off-by: Jens Axboe <axboe@kernel.dk>