Merge pull request #4 from libbitcoin/develop

Develop
Merge pull request #24 from libbitcoin/develop

travis: do no optimisation.
Merge pull request #27 from libbitcoin/develop

Travis build only master branch.
Remvoe dead code.
Swap libzmq source back to zmq repo (following merge).
Rename exaple config settings file.
Fix in output serializer, arg is seed not bitcount.
Draft readme, incomplete.
Fix comment typo.
Merge pull request #28 from evoskuil/develop

Update README, remove dead code