const contrib.go.opencensus.io/exporter/stackdriver.version

2 uses

	contrib.go.opencensus.io/exporter/stackdriver (current package)
		stackdriver.go#L293: var defaultUserAgent = fmt.Sprintf("opencensus-go %s; stackdriver-exporter %s", opencensus.Version(), version)
		stats.go#L54: 	version                   = "0.13.3"