bigquery/snippets: move ImportExport to an E2E test (#222)
bigquery/snippets: move ImportExport to an E2E test (#222)

This test takes a long time sometimes, and doesn't print any
intermediary output.

Print a log message very 5 minutes to work Travis's 10 minute timeout.

Move it to an E2E test, only run nightly.
adamyanliev/golang-samples,GoogleCloudPlatform/golang-samples,danicat/golang-samples,danicat/golang-samples,danicat/golang-samples,adamyanliev/golang-samples,adamyanliev/golang-samples,GoogleCloudPlatform/golang-samples,GoogleCloudPlatform/golang-samples,adamyanliev/golang-samples