Updated summer school links

You can now use the following links to refer to GF Summer School web pages:

- Latest summer school: http://school.grammaticalframework.org/
- 2009 summer school: http://school.grammaticalframework.org/2009
- 2011 summer school: http://school.grammaticalframework.org/2011
- 2013 summer school: http://school.grammaticalframework.org/2013

This is accomplished with DNS and web server configuration. No files have
been moved, so this does not break any existing links (except that
http://school.grammaticalframework.org/ now refers to the latest summer school
instead of the 2011 summer school).

gf-summer-school-2013.html

@@ -75,8 +75,8 @@ you can contact us now below.
 
 <H1>Previous summer schools</H1>
 <ul>
-<li><a href="http://www.grammaticalframework.org/summerschool.html">GF Resource Grammar Summer School</a> (2009) in Göteborg, Sweden</li>
-<li><a href="https://sites.google.com/site/gfschool2011/home">Second GF Summer School</a> (2011) in Barcelona, Spain</li>
+<li><a href="http://school.grammaticalframework.org/2009">GF Resource Grammar Summer School</a> (2009) in Göteborg, Sweden</li>
+<li><a href="http://school.grammaticalframework.org/2011">Second GF Summer School</a> (2011) in Barcelona, Spain</li>
 </ul>
 
 <H1>Contact</H1>

index.html

@@ -94,7 +94,7 @@ March 2012
 <tr><td>2010-12-23:<td><strong>GF 3.2 released!</strong>
     <a href="download/release-3.2.html">Release notes</a>.
 <tr><td>2010-12-22:<td>
-  <A HREF="http://school.grammaticalframework.org">GF Summer School</A>
+  <A HREF="http://school.grammaticalframework.org/2011">GF Summer School</A>
   in Barcelona, 15-26 August 2011.
 </table>