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/sets.go

@@ -215,19 +215,14 @@ Type: Blockchain
 AddToken(1)
 
 
-// Coordinator accounts, Idxs: 256, 257
-CreateAccountCoordinator(0) Coord
-CreateAccountCoordinator(1) Coord
-
 // close Block:0, Batch:0
-> batch // forge L1Coord{2}
+> batch
 
 CreateAccountDeposit(0) A: 500
 CreateAccountDeposit(1) C: 0
-CreateAccountCoordinator(0) C
 
 // close Block:0, Batch:1
-> batchL1 // freeze L1User{2}, forge L1Coord{1}
+> batchL1 // freeze L1User{2}, forge L1Coord{0}
 // Expected balances:
 //     Coord(0): 0, Coord(1): 0
 //     C(0): 0
@@ -263,13 +258,19 @@ CreateAccountDeposit(0) D: 800
 //     B(0): 400
 //     C(0): 0
 
+// Coordinator creates needed accounts to receive Fees
+CreateAccountCoordinator(1) Coord
+CreateAccountCoordinator(0) Coord
+// Coordinator creates needed 'To' accounts for the L2Txs
 CreateAccountCoordinator(1) B
+CreateAccountCoordinator(0) C
+
 
 Transfer(1) A-B: 200 (126)
 Transfer(0) B-C: 100 (126)
 
 // close Block:0, Batch:6
-> batchL1 // forge L1User{1}, forge L1Coord{2}, forge L2{2}
+> batchL1 // forge L1User{1}, forge L1Coord{4}, forge L2{2}
 // Expected balances:
 //     Coord(0): 10, Coord(1): 20
 //     A(0): 600, A(1): 280

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),
 		}