* Prevent unnecessary verification of parity blocks while reading erasure
coded file.
* Update klauspost/reedsolomon and just only reconstruct data blocks while
reading (prevent unnecessary parity block reconstruction)
* Remove Verification of (all) reconstructed Data and Parity blocks since
in our case we are protected by bit rot protection. And even if the
verification would fail (essentially impossible) there is no way to
definitively say whether the data is still correct or not, so this call
make no sense for our use case.
For files less than 'dataBlocks', erasure encoding would fail
with short data due to a bug in the implementation itself.
Relax the error return, even a single byte can be properly
erasure coded without issues.
Fixes#1413
