IxoPlayer: Add IxoDASHChunkIndexer.

Add class for parsing the result of combining the init and index
chunks of a DASH representation using libwebm. Provides an
NSMutableArray of chunk (Matroska Cluster element) ranges.

Includes script for dumping arrays of cluster ranges from WebM files
for building test data, and tests using the dumped cluster ranges as
expected output.

Change-Id: I5a81c69615d5c07817e934db931416c55f5000e5
7 files changed