Refactor Tile bytestream converters for TMDB

Digits for TMDB from bytestream are unpacked in the same time
when Tile digits are requested and upacked and put directly
into StoreGate ignoring standard conversion mechanism.
The same is done in the case of unpacking raw channels for TMDB.
This is not very good for AthenaMT (especially for scheduler).

Tile bytestream converters have been refactored
to unpack digits and raw channels for TMDB
only if they are requested (needed)
using standard conversion mechanism.

Unit tests for reading Tile digits and raw channels from bytestream
and the corresponding reference files have been updated accordingly.