Version 0.9.0

Minor release, only breaking change is cryptoUtils.signTransaction that now has a new signature. Another change is that PublicKey.from no longer needs an address prefixe but this should be backwards compatible.

Changelog

• Add a transaction digest helper, cryptoUtils.transactionDigest(tx, chainId)
• Simplify serialiser and remove prefix requirement from PublicKey parsing.
• Update all dependencies to latest versions
• Fix tests to run against appbase nodes