Enable Students to Download Their Tutorial Answers

The most common use of the tutorial.helpers package is to allow students to download their answers after they complete a tutorial. To enable this functionality, you need to, first, include library(tutorial.helpers) within the initial setup R code chunk and, second, add this line at the end of the tutorial:

```{r download-answers, child = system.file("child_documents/download_answers.Rmd", package = "tutorial.helpers")}
```

When students complete the tutorial, they will first be asked how long the tutorial took them to complete, in minutes. They will then be presented with the option to download a copy of their answers, in html format, to their Downloads folder. By default, the name of the downloaded file will be the id of the tutorial with _answers.html appended.

So, for example, a tutorial with an id equal to getting-started will generate a file called getting-started_answers.html.

The package provides functions like submissions_summary() and submissions_answers() to work with a collection of students answers.