Add excludeMempoolSpent Query Parameter to /blockchain/box/unspent/byAddress

[anon-yum2]

PR addressing issue: https://github.com/ergoplatform/ergo/issues/2093 by default excludeMempoolSpent set to false to not impact any current uses of the endpoint.

[anon-yum2]

Since filtering out UTXOs after receiving them from mempool may result in less than limit amount of UTXOs being returned (when there are more available), I have added recursive fetching for more UTXOs until the limit is hit or no more UTXOs are available. Will only fetch a limit of 200 UTXOs at a time.

[kushti]

@anon-yum2 compilation is failing now

[kushti]

import scorex.util.{ModifierId, bytesToId} => import scorex.util.{ModifierId, bytesToId, idToBytes}