Integrate purger to node

- Common
	- Add `IdxNonce` type used to track nonces in accounts to invalidate
	  l2txs in the pool
- Config
	- Update coordinator config will all the new configuration parameters
	  used in the coordinator
- Coordinator
	- Introduce the `Purger` to track how often to purge and do the job when
	  needed according to a configuration.
	- Implement the methods to invalidate l2txs transactions due to l2txs
	  selection in batches.  For now these functions are not used in favour
	  of the `Purger` methods, which check ALL the l2txs in the pool.
	- Call Invalidation and Purging methods of the purger both when the
	  node is forging (in the pipeline when starting a new batch) and when
	  the node is not forging (in coordinator when being notified about a
	  new synced block)
- L2DB:
	- Implement `GetPendingUniqueFromIdxs` to get all the unique idxs from
	  pending transactions (used to get their nonces and then invalidate
	  txs)
	- Redo `CheckNonces` with a single SQL query and using `common.IdxNonce`
	  instead of `common.Account`
- StateDB:
	- Expose GetIdx to check errors when invalidating pool txs
- Synchronizer:
	- Test forged L1UserTxs processed by TxProcessor
	- Improve checks of Effective values
- TxSelector:
	- Expose the internal LocalStateDB in order to check account nonces in
	  the coordinator when not forging.

config/config.go

@@ -35,13 +35,27 @@ type ServerProof struct {
 
 // Coordinator is the coordinator specific configuration.
 type Coordinator struct {
+	// ForgerAddress is the address under which this coordinator is forging
 	ForgerAddress     ethCommon.Address `validate:"required"`
 	ForgeLoopInterval Duration          `validate:"required"`
-	ConfirmBlocks     int64             `validate:"required"`
-	L2DB              struct {
+	// ConfirmBlocks is the number of confirmation blocks to wait for sent
+	// ethereum transactions before forgetting about them
+	ConfirmBlocks int64 `validate:"required"`
+	// L1BatchTimeoutPerc is the portion of the range before the L1Batch
+	// timeout that will trigger a schedule to forge an L1Batch
+	L1BatchTimeoutPerc float64 `validate:"required"`
+	L2DB               struct {
 		SafetyPeriod common.BatchNum `validate:"required"`
 		MaxTxs       uint32          `validate:"required"`
 		TTL          Duration        `validate:"required"`
+		// PurgeBatchDelay is the delay between batches to purge outdated transactions
+		PurgeBatchDelay int64 `validate:"required"`
+		// InvalidateBatchDelay is the delay between batches to mark invalid transactions
+		InvalidateBatchDelay int64 `validate:"required"`
+		// PurgeBlockDelay is the delay between blocks to purge outdated transactions
+		PurgeBlockDelay int64 `validate:"required"`
+		// InvalidateBlockDelay is the delay between blocks to mark invalid transactions
+		InvalidateBlockDelay int64 `validate:"required"`
 	} `validate:"required"`
 	TxSelector struct {
 		Path string `validate:"required"`
@@ -56,10 +70,24 @@ type Coordinator struct {
 		GasPriceDiv         uint64   `validate:"required"`
 		ReceiptTimeout      Duration `validate:"required"`
 		IntervalReceiptLoop Duration `validate:"required"`
+		// IntervalCheckLoop is the waiting interval between receipt
+		// checks of ethereum transactions in the TxManager
+		IntervalCheckLoop Duration `validate:"required"`
+		// Attempts is the number of attempts to do an eth client RPC
+		// call before giving up
+		Attempts int `validate:"required"`
+		// AttemptsDelay is delay between attempts do do an eth client
+		// RPC call
+		AttemptsDelay Duration `validate:"required"`
 	} `validate:"required"`
 	API struct {
 		Coordinator bool
 	} `validate:"required"`
+	Debug struct {
+		// BatchPath if set, specifies the path where batchInfo is stored
+		// in JSON in every step/update of the pipeline
+		BatchPath string
+	}
 }
 
 // Node is the hermez node configuration.