Transaction: deprecate Tx signing methods
TxBuilder: Initial commit and tests
TxBuilder: use data fixtures for invalid tests
TxBuilder: transform all signatures once
TxBuilder: use build/buildIncomplete over boolean
Wallet: use TxBuilder instead
tests: add TxBuilder pubKey test fixture
TxBuilder: add invalid nulldata case
TxBuilder: sign after error checking
TxBuilder: remove unnecessary assert
index: add TransactionBuilder
tests: integration test to use TxBuilder
TxBuilder: add sequence number passthrough
TxBuilder: adds fromTransaction impl. and basic tests
tests: add P2SH multisig example case
TxBuilder: re-order functions to project standard
Merge pull request #244 from dcousens/txbuilder

Transaction Builder
tests: code formatting
Wallet: remove txId:index storage for spent outputs
Wallet: store txHash, vout separately instead of "from: txid:vout"