fix issue where go 1.8 would add duplicate Auth header

apigee_sync.go

diff --git a/apigee_sync.go b/apigee_sync.go
index d6b3a19..aa816bb 100644
--- a/apigee_sync.go
+++ b/apigee_sync.go
@@ -86,12 +86,6 @@
 	}
 }
 
-func Redirect(req *http.Request, _ []*http.Request) error {
-	req.Header.Add("Authorization", "Bearer "+tokenManager.getBearerToken())
-	req.Header.Add("org", apidInfo.ClusterID) // todo: this is strange.. is it needed?
-	return nil
-}
-
 func addHeaders(req *http.Request) {
 	req.Header.Add("Authorization", "Bearer "+ tokenManager.getBearerToken())
 	req.Header.Set("apid_instance_id", apidInfo.InstanceID)

snapshot.go

diff --git a/snapshot.go b/snapshot.go
index ae667bf..5a1c576 100644
--- a/snapshot.go
+++ b/snapshot.go
@@ -140,12 +140,15 @@
 	log.Infof("Snapshot Download: %s", uri)
 
 	client := &http.Client{
-		CheckRedirect: Redirect,
+		CheckRedirect: func(req *http.Request, _ []*http.Request) error {
+			req.Header.Set("Authorization", "Bearer "+tokenManager.getBearerToken())
+			return nil
+		},
 		Timeout:       httpTimeout,
 	}
 
 	//pollWithBackoff only accepts function that accept a single quit channel
-	//to accomadate functions which need more parameters, wrap them in closures
+	//to accommodate functions which need more parameters, wrap them in closures
 	attemptDownload := getAttemptDownloadClosure(client, snapshot, uri)
 
 	pollWithBackoff(quitPolling, attemptDownload, handleSnapshotServerError)