[google-analytics] How do you trigger all the ecommerce calls?

[SegmentDestinationsBot]

Migrated from #8 by @kmiyashiro

https://github.com/segment-integrations/analytics.js-integration-google-analytics/blob/master/lib/index.js#L74-L85

The docs explain how to trigger add/remove product to cart and Completed Order events, but not all of the ones in this integration.