Closes #218. AlertEvent.Timestamp as int64 instead of int

Also created a PR in the upstream repo to fix this:

https://github.com/yfronto/newrelic/pull/61

.goreleaser.yml

@@ -8,6 +8,7 @@ builds:
       - darwin
       - linux
     goarch:
+      - 386
       - amd64
 
 archive:

vendor/github.com/yfronto/newrelic/alert_events.go

@@ -10,7 +10,7 @@ type AlertEvent struct {
 	EntityID      int    `json:"entity_id,omitempty"`
 	Priority      string `json:"priority,omitempty"`
 	Description   string `json:"description,omitempty"`
-	Timestamp     int    `json:"timestamp,omitempty"`
+	Timestamp     int64  `json:"timestamp,omitempty"`
 	IncidentID    int    `json:"incident_id"`
 }