Use deltas for all edict fields

[casey]

Edict id, amount, and vout are all be deltas. Id is always a delta, amount is a delta if the ID is the same as the last, and output is a delta if the amount is the same as the last.

[sondotpin]

How Id can deltas?
what is delta of { height: 3, index 1} and { height: 5, index 3}

[casey]

Under realistic circumstances, a block will never have more than 2**16 transactions, so an ID can be encoded as a single number as height << 16 | index.

[casey]

Edicts are processed in order, so we can't fully reorder them. However, we can reorder edicts by id. So it looks like the best bet is do delta encode edict IDs, but not amounts.