TxSel integrated with L2DB, Add L1CoordTx creation

- GetL2TxSelection & GetL1L2TxSelection integrated with dbs
- Create L1CoordinatorTx of type CreateAccountDeposit when a L2
requires it (and the AccountCreationAuth exists)

common/accountcreationauths.go

@@ -11,6 +11,6 @@ import (
 type AccountCreationAuth struct {
 	Timestamp time.Time
 	EthAddr   ethCommon.Address
-	BJJ       babyjub.PublicKey
+	BJJ       *babyjub.PublicKey
 	Signature []byte
 }