Timeshift buffering

      +---------+     +---------+     +-------+
      | httpsrc |     | buffer  |     | demux |
      |        src - sink      src - sink     ....
      +---------+     +----|----+     +-------+

In this mode, a fixed size ringbuffer is kept to download the server content. This allows for seeking in the buffered data. Depending on the size of the ringbuffer one can seek further back in time.

This mode is suitable for all live streams. As with the incremental download mode, buffering messages are emited along with an indication that timeshifting download is in progress.