SDK / exoplayer

- Remove simple variant. Maintaining both simple + full is
  unnecessary effort.
- Remove need to specify content id in Sample definition,
  except where it's actually required (for DRM requests in
  the Widevine GTS samples)

Also add parseMp4vFromParent and return the track's duration in parseTrak.

This is in preparation for adding a non-fragmented MP4 extractor.

If the timesource track renderer ends, but other track renderers
haven't finished, the player would get stuck in a pending state.
This change enables automatic switching to the media clock in the
case that the timesource renderer has ended, which allows other
renderers to continue to play.

Add a utility for converting named atom types to integers.

Add atom types for non-fragmented MP4 parsing.

Issue: #268

These may occur in VOD streams where a representation's data
is small enough not to require segmentation or an index. For
example subtitle files.

Issue: #268

SampleExtractor will initially only be implemented by FrameworkSampleExtractor
which delegates to a MediaExtractor, but eventually it will also be implemented
by additional extractors.

The sample extractor can be used as a source of samples via DefaultSampleSource.

Issue: #268

This may be painful in terms of applications having to change their
imports. Sorry about that.

Merge dev-hls -> dev

dev -> dev-hls

Also added clamping to getSegmentNum in one case where
it was not already implemented, and defined this behavior
property in the getSegmentNum javadoc.

Issue: #262

This makes the calculation correct for the case where periodDurationMs
does not divide exactly into durationMs.

Fixed wrong calculation of last segment number when using segment templa...

Fixed wrong calculation of last segment number when using segment template without segment timeline.

dev -> dev-hls

Without this, the byte is cast as follows (in bits) if the top
byte is set:

10000010 -> 1000000000000000000000000000010

This works because we then always shift at least one bit left,
and only look at the bottom 8 bits of the result. It's confusing
though. It's clearer if the cast to int gives just adds zeros to
the front, like:

10000010 -> 0000000000000000000000010000010

Fix a signed right shift issue in BitArray.readUnsignedByte()

Make BitArray.readUnsignedByte() a bit more clear by using int value instead of byte to prevent unnecessary convert from int to byte.

Fix an issue in BitArray.readUnsignedByte() returns incorrect value when bitOffset is not zero and data[byteOffset + 1] starts with bit 1.
This is caused by signed right shift, the fix is simply to make it unsigned right shift.

dev -> dev-hls

FrameworkSampleSource with FileDescriptor

Move Closed Captions processing to Eia608TrackRenderer. Use TextRenderer interface for captions. Sort captions based on video frames DTS. Add better control characters and special characters in basic North American character set support. Fixes #156