mw/autopath: integration test with erratic (#930)

Add integration test with erratic. For this erratic now also returns an
autopath searchpath. This tests the whole chain; i.e registring a
searchfunction and calling that from autopath.

This tests does a autopathing domain and a non-autopathing one.

middleware/erratic/setup.go

@@ -28,6 +28,9 @@ func setupErratic(c *caddy.Controller) error {
 		return e
 	})
 
+	// Also register erratic for use in autopath.
+	dnsserver.GetConfig(c).RegisterHandler(e)
+
 	return nil
 }