README: add link to https://git.github.io

Author: chriscool

_includes/README.md

@@ -2,7 +2,8 @@
 
 This homepage is maintained by editing files in the
 [git/git.github.io](https://github.com/git/git.github.io) repository on
-GitHub.
+GitHub. It is then published on the
+[https://git.github.io](https://git.github.io) GitHub page.
 
 It is meant to be edited collaboratively like a wiki, except that
 instead of a web form, you get to use a text editor and git. What could