We always assumed that text stream started at zero in the text chunker.
This meant that if the text stream started later than zero (like in a
live stream) we would generate a lot of empty segments.
Instead the text chunker will assume that segments should be adjusted
to align with multiple of segment duration. The text chunker will assume
that an earlier component in the pipeline (i.e. text padder) will ensure
that the first sample has the time that we want to start segments at
(even it needs to add an empty sample).
Issue #416
Change-Id: Ie45844354d6e9448787cae896841b5ab31721ed6
5f072e3b08