There was a bug when getting unspent outputs that would include an output
that was spent in the mempool in addition to the new output with the change
address. This lead to a balance having an output counted twice towards the
end balance. The solution is to have the isSpent method for the address service
to also include if the output was spent in the mempool, as the isSpent
method exposed from bitcoind only includes if the output was spent in a block.
d9b2a0969b