add Blockchain
Add this blockchain and start syncing it. (or call @ref addBlockchain do do both). You should determine either earliestHeight or earliestDate, possibly via Rostrum, or you may be in for a very long sync operation.
Parameters
earliest Height
There is no wallet activity before this block height. Pass null if you don't know.
earliest Date
There is no wallet activity before this date in epoch seconds. Pass null if you don't know.