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
Merge pull request #262 from dcousens/wallref

processTx considered harmful followup
Add viacoin support
Merge pull request #276 from btcdrak/viacoin

Add viacoin support
Transaction: use isFinite instead over typeof number
Transaction: use isFinite over Number.isFinite
Wallet: fix missing variable utxo
Wallet: add missing variable wallet
tests: Wallet test was not comprehensive
tests: remove sinon, breaks in weird circumstances