Fabo/track failing txs (#201)

* track failing txs

* remove dead code

* linted

lib/controller/transaction/index.js

@@ -1,5 +1,6 @@
 const { getMessage } = require('./messageConstructor')
 const { networks } = require('../../networks')
+const Sentry = require('@sentry/node')
 
 global.fetch = require('node-fetch')
 
@@ -39,8 +40,13 @@ async function broadcast(tx) {
       success: true
     }
   } catch (e) {
+    Sentry.withScope(function(scope) {
+      scope.setExtra('api_url', networks[tx.networkId].api_url)
+      scope.setExtra('transaction', tx.signedMessage)
+      Sentry.captureException(e)
+    })
     return {
-      error: e,
+      error: e.message,
       success: false
     }
   }