This commit expands the data returned by the current GetCurrentHeight
to also return the current best block hash, expanding the method into
GetBestBlock. Additionally, the current best BlockHash is also now
displayed within the GetInfo RPC call.
This commit adds the first concrete implementation of the
WalletController interface: BtcWallet. This implementation is simply a
series of wrapper functions are the base btcwallet struct.
Additionally, for ease of use both the BlockChain IO and Signer
interface are also implemented by BtcWallet. Finally a new WalletDriver
implementation has been implemented, and will be register by the init()
method within this new package.
