Merge pull request #6 from Bit-Wasp/datadirgenerator

DataDirGeneratorInterface

allow skipping wait for rpc/startup

allow overriding the Client driver

Merge pull request #5 from Bit-Wasp/no-buffertools

remove buffertools

Merge pull request #4 from Bit-Wasp/spectrum-test-nbobtc

spectrum test multiple nbobtc versions

Merge pull request #3 from Bit-Wasp/license

add license