NFD

This is a decision from 20140221 conference call.

The original reason for using fixed length fields for FragIndex and FragCount is the concern on encoding performance.
ndn-cpp-dev has an efficient EncodingBuffer, which makes the above reason invalid.

There is no disadvantage in moving to variable length nonNegativeNumber encoding.

Let's be more consistent and update all counters to nonNegativeInteger... Less chances of having portability problems.

Also about wrapping around. Is it even feasible with 8-byte number? You gave me an argument before that it will take many years to do so...

NdnlpSequence is not a counter. It should not be defined as nonNegativeInteger.

There is no known portability problem of using a fixed length field.

what is sequence number then? Is it fragment ID (which is unique for all fragments) or real sequence (which is increased by one for all segments)?

20140224 conference call decides not to change NdnlpSequence field.