Major Description
I have some proposed changes for the spec in the Object Container Files section.
The fixes are:
1) call out explicitly that when it says long, it means avro-encoded long.
2) since the implementations are serializing the metadata as an avro map, this map should be followed by a block size of 0 (consistent with avro map encoding)
3) fix the example header schema so it passes JSONLint (it had an extra comma after the last array value).
Number 2 above is something I'm not sure about, because I don't know if it's a compatible change... I hope it does not break any implementations.