attempt to add http range request support for datastream download (e.g., support seeking in jplayer) PRELIMINARY
fix format error for content range response
correct range calculation for full size request; remove debug print statement, add some debug logging
better support and tests for http range requests on raw datastream content
unit test cleanup
add note to changelog about basic http range request support
Merge branch 'feature/range-request-support' into develop
set version to 0.22.0 final
document new validate-checksums script in changelog
Merge branch 'release/0.22' into develop