Integration with binder

binder is an amazing tool for reproducible research. It would be great if we could make it easier for workflowr users to integrate binder into their research projects.

An idea for a function, e.g. wflow_use_binder(), would perform the following steps:

1. Search all the published R Markdown files for library() calls (and related pkg usage, e.g. pkg::)
2. Create and commit a configuration file that is supported by repo2docker.
3. Add a binder link to README.md and to the website (either index.Rmd or the navbar in _site.yml)

The first step is the weakest. I could imagine improving it in multiple ways. One would be to have each Rmd file automatically write its dependencies after running sessionInfo(). Alternatively, wait for the package manager functionality (#128) to be integrated before making this any more complicated.

I'm open to ideas and suggestions.

cc: @seabbs @sdhutchins

xref: Tweet

Start by reviewing the proposed wflow_use_binder() workflow and the published R Markdown files whose dependencies it would inspect. Check README.md, index.Rmd, and _site.yml for the locations where a Binder link could be added, along with the repo2docker configuration requirements. Done means the integration approach is agreed, dependencies are represented, configuration is committed, and the links appear in the requested project locations.