ConceptPending/proveit — pull request #4 by zw (2014-03-26 17:33:12+00:00)
Title: Adapt to hash compatibly with draft standard

Namely [this one] [s11n] which you've raised no objections to and hopefully approve of! :)

[s11n]: https://github.com/olalonde/proof-of-liabilities#serialized-data-formats-work-in-progress--draft

This is with a view to adding support for JSON de/serialisation in a further pull request.

Also:
* accept uid/nonce as alternative to externally produced hash, to encourage
standard hashing format
* be sure to provide original data to validation, rather than feeding
data obtained from tree right back in
* use `sum` not `value`, and `hash` not `hashdigest`, (where that doesn't
conflict with builtins) to match terminology in standard and in other implementations
* update README to match, including suggesting following draft standard
* change test to construct `Node` with uid/nonce leaves, since internal node
hashing already tests externally-provided-hash constructor
* add `__str__` for slightly pretty-printing `Node`
* be more verbose in test output
* update link to point to preferred, more verbose/pretty description