- added an option (on by default) to prevent a witness from signing two
blocks in a row because this most likely indicates they have been cut
off from the network.
- added an option where a witness will not produce a block if the
witness participation rate is below a configurable threshold (default
to 33%)
- this is a major refactor of the code and may have broken some behavior
in the wallet or witness nodes.
- this commit changes the serialization of operations
- the chain_tests pass
