WIP commit. More ODIDMediaEngine live support and availableSeekRange.dlna.org support

Added classes DLNAAvailableSeekRangeRequest and DLNAAvailableSeekRangeResponse
 for processing getAvailableSeekRange.dlna.org and availableSeekRange.dlna.org.

ODIDMediaEngine.get_resources_for_item() is updated to produce MediaResources
 according to newly-defined resource.info properties "live" and
 "limited-operation-mode" and the state of the ODIDLiveSimulator.

 If the live simulator is in a not-started or live state:

  o The res@size and res@duration are not set
  o The limited operation,S-0/S-N, sender-paced & operation flags are set
    according to the state of the live sim.

 If the live simulator is in the stopped state:

  o The res@size and res@duration are set to the amount of content in the
    simulated TSB.
  o The full random access bits are set for time-seek and byte-seek
    (a-val and b-val set to 1)
  o Limited operation bits are not set

ODIDDataSource.preroll() is updated to support requests against live-mode
 resources.

  o Range/TimeSeekRange requests are checked against the effective time range
    reported by the live simulator when the resource is configured for live
    mode (limited random access mode 0).
  o Added support for DTCPCleartextRequest. It produces a
    DLNAAvailableSeekRangeResponse using the values return from the live sim.
  o A lot of the logic had to be restructured to deal with the live support.

Many index file methods from ODIDMediaEngine and ODIDDataSource were
 moved to ODIDUtil since many of the operations now have to be performed from
 both places. Cleaned up some of the method signatures in the process.
 e.g. Most now take File objects instead of file paths (strings).

ODIDLiveSimulator updated to support auto-stop behavior, periodic range
 reporting (for debugging), and a variety of methods added for accessing
 the current time/range values.

Compiles, but requires testing.