Add notes referencing 2nd edition (#638)

README.md

@@ -1,8 +1,9 @@
-[![Build Status](https://travis-ci.org/jrnold/r4ds-exercise-solutions.svg?branch=master)](https://travis-ci.org/jrnold/r4ds-exercise-solutions)
-[![Lifecycle: stable](https://img.shields.io/badge/lifecycle-stable-brightgreen.svg)](https://www.tidyverse.org/lifecycle/#stable)
+[![Lifecycle: superseded](https://img.shields.io/badge/lifecycle-superseded-blue.svg)](https://lifecycle.r-lib.org/articles/stages.html#superseded)
 
 # Exercise Solutions to R for Data Science
 
+These are solutions to the **1st edition** of R for Data Science. The solutions to the 2nd edition of [R for Data Science](https://r4ds.hadley.nz/) are available at [R for Data Science (2e) - Solutions to Exercises](https://mine-cetinkaya-rundel.github.io/r4ds-solutions/).
+
 This repository contains the code and text behind the [Solutions for R for Data Science](https://jrnold.github.io/r4ds-exercise-solutions/), which, as its name suggests, has solutions to the the exercises in [R for Data Science](https://r4ds.had.co.nz/) by Garrett Grolemund and Hadley Wickham.
 
 The R packages used in this book can be installed via
@@ -12,9 +13,7 @@ devtools::install_github("jrnold/r4ds-exercise-solutions")
 
 ## Contributing
 
-Contributions welcome! Notice a wrong answer, typo, bug, or have an alternative/better solution, open a new [issue](https://github.com/jrnold/r4ds-exercise-solutions/issues ) or [pull request](https://github.com/jrnold/r4ds-exercise-solutions/pulls).
-
-Please note that the 'R4DSSolutions' project is released with a [Contributor Code of Conduct](.github/CODE_OF_CONDUCT.md). By contributing to this project, you agree to abide by its terms.
+Work on this repo has effectively stopped since the 2nd edition of R for Data Science has been published. Please direct your contributions to [R for Data Science (2e) - Solutions to Exercises](https://mine-cetinkaya-rundel.github.io/r4ds-solutions/).
 
 ## Build