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Message: allow base64 strings as input
tests: avoid unnecessary .ok
Merge pull request #266 from dcousens/mesb64

Message: allow base64 strings as input
tests: code formatting
Wallet: remove txId:index storage for spent outputs
Wallet: store txHash, vout separately instead of "from: txid:vout"
bufferutils: add Buffer reverse
Wallet: revert 2f00c9a
Wallet: consistent variable naming
Wallet: rename outputs to unspentsMap
Wallet: refactor to use Array unspents solely, deprecating unspentsMap
tests: avoid use of deprecated APIs
TxBuilder: add failing test for non-zero vin inputs
TxBuilder: fix invalid txin.index usage for non-zero vin inputs
TxBuilder: avoid unnecessary recalculation of prevOutScript data
Transaction: throw if sequence is not a number
TxBuilder: add test for missing redeemScript if P2SH
TxBuilder: limit signatures depending on scriptType