integration tests: add brainwallet/README examples
integration tests: refactor helloblock P2SH spending test
integration tests: add example OP_RETURN transaction
integration tests: add stealth address example
integration tests: add more basic examples
integration tests: rename all files to basic/advanced/multisig
integration tests: test description rephrasing
README: remove examples and link to integration tests
integration tests: fix 2-of-2 spend address network
integration tests: merge #312 test equivalent
integration tests: add timeout for 2-of-2 spend
README: fix test line numbers
README: s/inttests/master/
Merge pull request #302 from bitcoinjs/inttests

More integration tests
remove base58check

Use bs58check package solely from here on.
rename Message to message
crypto: remove Hmac* exposure in API
crypto: re-work fixtures for simplicity
remove deprecated functionality
Transaction/TxBuilder: move all param coercion to TxBuilder