Dev/robin/8241 accumulator prove and verify

[robinbryce]

MMR draft alignment changes

The primary change here is to make our consistency proofs and inclusion proofs work in terms of the accumulator defined in the paper referenced by the COSE Receipts MMRIVER draft. And generaly include full support for COSE Recieipts

It also cleans up various algorithm implementations and checks that the draft algorithm implmentations and our go lang immplementation both meet the test vectors published by the draft.

Because it remains useful to be able to do so, I have retained the original variants of algorithms that worked with mmr "bagged" peaks. Some algorithm implementations I think we can remove altogether, but in this pr have not been deleted. Instead they are used in tests which show the "old" versions match the "new" versions

So in summary

• bagged.go means a file that has things only relevant for MMR bagged peaks
• old.go means a file that has things that are retained for compatibility testing but which are now "depricated"
• Bagged() means the function is only relevant for working with MMR bagged peaks
• Old() means the function is depricated, retained for compatibility testing

I've run all the local unit and integration tests. I've also run the integration tests in forestrie and checked that the arrangements for dealing with the change in consistency proofs work at that level. More testing for this on the forestrie side will be required before taking a release of go-datatrails-merklelog/mmr which has these changes.