Fix TxProcessor TokenID use &updates at Til&Common

- Til
  - tests that were using `til.SetBlockchainMinimumFlow0` have been
updated, as now the L1CoordinatorTxs are placed simulating TxSelector
creation (when needed, not before)
  - Add `EthSk` to `tc.User` to allow to sign `AccoutCreationAuths` at
the tests flows
- TxProcessor
  - for L2Txs get TokenID from tx.FromIdx Account.TokenID instead than
  - update tests vectors for new values
from tx.TokenID (which not always is set)
- Common
  - move TxIDsFromL2Txs & TxIDsFromPoolL2Txs from `coordinator` to
`common` to allow usage from other packages

test/til/txs.go

@@ -123,6 +123,7 @@ type Account struct {
 type User struct {
 	Name     string
 	BJJ      *babyjub.PrivateKey
+	EthSk    *ecdsa.PrivateKey
 	Addr     ethCommon.Address
 	Accounts map[common.TokenID]*Account
 }
@@ -696,6 +697,7 @@ func (tc *Context) generateKeys(userNames []string) {
 		u := User{
 			Name:     userNames[i-1],
 			BJJ:      &sk,
+			EthSk:    &key,
 			Addr:     addr,
 			Accounts: make(map[common.TokenID]*Account),
 		}