Now the Cue settings are a generic object that is parsed in WebVTT.
This will allow setting the settings in different parsers without having
to use WebVTT-specifics.
Change-Id: I36689bec725bd2e515af962b7174fc5977f96fa2
This sets the groundwork for more generic text cues by having a more
generic object for the settings and the body. This also changes the
TextSample to be immutable and accepts the fields in the constructor
instead of using setters.
Change-Id: I76b09ce8e8471a49e6bf447e8c187f867728a4bf