while there, rename a data member of Item to match libtiger, makes it easier

also expose start time as a parameter for when the stream is not seekable

fix start granpos not being actually set to anything else than 0

by moving the actual overlay rendering till later, using a subclass
 of ImageProducer, in order to:
 - avoid slowing down the buffer passing to the sink, which would
   increase the likelihood a frame would arrive late, and be dropped
 - avoid the rendering altogether when a frame is late, and dropped

 while you are rendering the items list

 JDK 1.1.6 from Sun; if it can't be used, continue without audio

 so cortado may be used without kate support, for a smaller download

factor a bit the status bar button related code

 being played has subtitles available

 jtiger renderer is dirty - this plays nice with high nominal fps
 videos with lots of drop frames

Avoids displaying duplicate frames, except once per second.

 record the start to offset from, not just the first time, or seeking
 will cause reported position to be wrong.

 so that the -ov- version now works again; while there, also look
 at Theora timestamps.

 using jheora/jorbis directly

 versions of Cortado may not have all of them.

 decide not to render it again when it is not necessary

 now added with a fake sink; this allows playing music with lyrics,
 and paves the way for exposing timed text to Javascript.

 a stream's MIME type - this allows the Kate decoder to add language
 and category fields, and in turn allows the pipeline to select a
 Kate stream by language/category before the decoder is started,
 avoiding missing subtitles starting at time 0.