blob: always update data and index file simultaneously.

This fixes bug when datafile index is not updated during overwrite.

Also removed cfg.bsize handling for now.
hash: simplified hash lookups

Now that we have only one rctl per hash we can greatly simplify hash.

Also while here speedup l2hash: do not look in hash in case l2hash
lookup failed.
And fix stats in case of errors: update hashed only if err == 0
XXX
blob: less extensive logging