Add note to README pointing to 1.0 issue (#422)

Author: KyleAMathews

README.md

@@ -21,6 +21,8 @@ Build sites like it's 1995. Files are translated into HTML pages at the
 same position within the file system. Add a markdown file at `/docs/index.md` and
 it'll be converted to `/docs/index.html`.
 
+*[We've started work on a 1.0 release of Gatsby!](https://github.com/gatsbyjs/gatsby/issues/419)*
+
 ![live-reloading example](http://zippy.gfycat.com/UltimateWeeklyBarebirdbat.gif)
 
 ## Goals