Updates marian-dev and ssplit submodules to point to the upstream
commits which implements the following:
- marian-dev: encodeWithByteRanges(...) to get source token byte-ranges
- ssplit: Has a trivial sentencesplitter functionality implemented, and
now is faster to benchmark with marian-decoder.
This enables a marian-decoder replacement written through ssplit in this
source to be benchmarked constantly with existing marian-decoder.
Nits: Removes logging introduced for multiple workers, and respective
log statements.
