Add RTD link to README.

diff --git a/README.md b/README.md
index ef81cf5c62255fdd20765380cd9c92898e5b6671..f2c7b151101483914c339c12764b9ce3ba0f8bf8 100644 (file)
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@ Inform Beginner's Guide
 Introduction
 ------------
 
-This repository contains the sources for the
+This repository contains the sources for an updated version of the
 [Inform Beginner's Guide](http://www.firthworks.com/roger/IBG.html),
 henceforth known as the IBG.  This version is in a new source format that's
 more version-control and contributor-friendly:
@@ -27,6 +27,9 @@ the 4th edition will be prepared.  The rationale for a 4th edition is:
 * Some old web links have gone away, to be replaced by new and better
   ones.
 
+If you want a preview of how the online HTML version of the new guide
+looks, you can find it [here](http://inform-beginners-guide.readthedocs.org).
+
 Building from source
 --------------------