- StateDB
- Update GetIdxByEthAddrBJJ to return ErrToIdxNotFound when idx not found, so can be checked at upper levels
- TxSelector
- rm CoordIdxsDB that is no longer needed (also related methods)
- add `getCoordIdx` method to get the Coordinator Idx for a given TokenID
- Update coordinator account creation related to new TokenIDs from L2Txs
- Reorganize GetL1L2TxSelection
- return CoordIdxs used in the selection
- Update go-merkletree version which avoids marshaling Siblings to json
with 'null' value in case of empty array