existing cluster tests working with RH being updated on changes, scanned on gets
RoleHistoryWriter: has part of a resource stream reader, but string->byte conversion got in the way
rename roles so the index matches the name
RoleHistoryWriter saves state in JSON, adds a resource path reader for tests
TestHistoryRW tests basic r/w round tripping
Core role history save/load works
save, thaw and building of node list works on thaw -but node address comparisons don't work on thawed data -their source is not a string.