feat: add transaction batching module

feat: plugin sendCoins batching support
feat: batching processing on poller
feat: mock-wallet batching
fix: bitcoin tx batching
fix: transaction batching db table

lib/plugins.js

@@ -22,6 +22,7 @@ const machineLoader = require('./machine-loader')
 const customers = require('./customers')
 const commissionMath = require('./commission-math')
 const loyalty = require('./loyalty')
+const transactionBatching = require('./tx-batching')
 
 const { cassetteMaxCapacity, CASH_OUT_DISPENSE_READY, CONFIRMATION_CODE } = require('./constants')
 
@@ -277,6 +278,15 @@ function plugins (settings, deviceId) {
   }
 
   function sendCoins (tx) {
+    if (wallet.supportsBatching(settings, tx.cryptoCode)) {
+      return transactionBatching.addTransactionToBatch(tx)
+        .then(() => ({
+          batched: true,
+          sendPending: false,
+          error: null,
+          errorCode: null
+        }))
+    }
     return wallet.sendCoins(settings, tx)
   }