Use the visual editor (hadley#923)

* Sentence wrap + visual editor Rmd style updates

* Move files not called in bookdown.yml to extra

* UK spelling + canonical source + sentence wrap

* Rename .rmd -> .Rmd

* Sentence wrap + visual editor Rmd style

* Fix capitalization

communicate.Rmd

@@ -1,32 +1,25 @@
-# (PART) Communicate {-}
+# (PART) Communicate {.unnumbered}
 
 # Introduction {#communicate-intro}
 
-So far, you've learned the tools to get your data into R, tidy it into a form convenient for analysis, and then understand your data through transformation, visualisation and modelling. However, it doesn't matter how great your analysis is unless you can explain it to others: you need to __communicate__ your results.
+So far, you've learned the tools to get your data into R, tidy it into a form convenient for analysis, and then understand your data through transformation, visualisation and modelling.
+However, it doesn't matter how great your analysis is unless you can explain it to others: you need to **communicate** your results.
 
 ```{r echo = FALSE, out.width = "75%"}
 knitr::include_graphics("diagrams/data-science-communicate.png")
 ```
 
 Communication is the theme of the following four chapters:
 
-* In [R Markdown], you will learn about R Markdown, a tool for integrating
-  prose, code, and results. You can use R Markdown in notebook mode for 
-  analyst-to-analyst communication, and in report mode for 
-  analyst-to-decision-maker communication. Thanks to the power of R Markdown
-  formats, you can even use the same document for both purposes.
-
-* In [Graphics for communication], you will learn how to take your exploratory
-  graphics and turn them into expository graphics, graphics that help the
-  newcomer to your analysis understand what's going on as quickly and 
-  easily as possible.
-
-* In [R Markdown formats], you'll learn a little about the many other varieties
-  of outputs you can produce using R Markdown, including dashboards, websites,
-  and books.
-
-* We'll finish up with [R Markdown workflow], where you'll learn about the
-  "analysis notebook" and how to systematically record your successes and 
-  failures so that you can learn from them.
-
-Unfortunately, these chapters focus mostly on the technical mechanics of communication, not the really hard problems of communicating your thoughts to other humans. However, there are lot of other great books about communication, which we'll point you to at the end of each chapter.
+-   In [R Markdown], you will learn about R Markdown, a tool for integrating prose, code, and results.
+    You can use R Markdown in notebook mode for analyst-to-analyst communication, and in report mode for analyst-to-decision-maker communication.
+    Thanks to the power of R Markdown formats, you can even use the same document for both purposes.
+
+-   In [Graphics for communication], you will learn how to take your exploratory graphics and turn them into expository graphics, graphics that help the newcomer to your analysis understand what's going on as quickly and easily as possible.
+
+-   In [R Markdown formats], you'll learn a little about the many other varieties of outputs you can produce using R Markdown, including dashboards, websites, and books.
+
+-   We'll finish up with [R Markdown workflow], where you'll learn about the "analysis notebook" and how to systematically record your successes and failures so that you can learn from them.
+
+Unfortunately, these chapters focus mostly on the technical mechanics of communication, not the really hard problems of communicating your thoughts to other humans.
+However, there are lot of other great books about communication, which we'll point you to at the end of each chapter.

contribute.Rmd

@@ -0,0 +1,19 @@
+# Contributing
+
+This book has been developed in the open, and it wouldn't be nearly as good without your contributions.
+There are a number of ways you can help make the book even better:
+
+-   If you don't understand something, please [let me know](mailto:[email protected]).
+    Your feedback on what is confusing or hard to understand is valuable.
+
+-   If you spot a typo, feel free to edit the underlying page and send a pull request.
+    If you've never done this before, the process is very easy:
+
+    -   Click the edit this page on the sidebar.
+
+    -   Make the changes using GitHub's in-page editor and save.
+
+    -   Submit a pull request and include a brief description of your changes.
+        "Fixing typos" is perfectly adequate.
+
+    -   If you make significant changes, include the phrase "I assign the copyright of this contribution to Hadley Wickham" - I need this so I can publish the printed book.