Docs follow-up Entity Translation API improvements

Doc pieces from #6 that are still relevant.

Reading the comments and seems agreement in #6 is the way to go. #25 being a reroll of it.

I skimmed the issue and then read the patch. I checked that all comments have been addressed and they have been. The changes here are for grammar and coding standards. There are no changes for any of the problems or proposed resolution listed in the Issue Summary, although it was probably true when the issue was created. Other than that I think this can be committed.

I'll wait a day or two for any feedback.

Committed 72f1f1f and pushed to 10.1.x. Thanks!

Automatically closed - issue fixed for 2 weeks with no activity.