Transaction: data driven tests
Transaction: add sequence parameter to addInput
Transaction: re-adds getHash as a pure hash
Transaction: add hash as addInput parameter
Transaction: remove untestable assert

Also changes the fromBuffer sanity test to use a clearer message that is
taken from the fixtures.
Transaction: move constants to Transaction
Transaction: improve hash length checking + tests
Network: use capitalization
Merge pull request #216 from dcousens/addrser

Network: use capitalization
Merge pull request #214 from dcousens/txtests

Transaction tests
wallet: Move dust and fee per kb into networks.js
Fix bitcoin dustThreshold and feePerKb values
Move fee estimation into networks.js
Add fee estimation functions for dogecoin and litecoin
Network specific constants reference the latest tags
Network estimateFee tests no longer relies on fixtures