cbor serialization of big integers (Uint) is undefined

[whyrusleeping]

I really thought we had this written down at some point as using a cbor big int, but i can't seem to find it.

In any case, We should use cbor big ints here (its an extension). It costs us one extra byte for the tag, but means other CBOR parsers can more easily understand our datastructures.

[whyrusleeping]

Also rather annoying that the cbor spec refers to the integer encoding for big ints as 'network byte order'. Is that really easier to type than 'big endian' ?