Added new donor.

svn path=/trunk/; revision=22563

donate/donors/donors-2012.en.xml

@@ -59,6 +59,7 @@
     <donor date="2012-12-31">Torsten Loehr</donor>
     <donor date="2012-12-31">Ulrich Walter</donor>
     <donor date="2012-12-31">Uwe Henschel</donor>
+    <donor date="2012-02-24">Walter van Holst</donor>
     <donor date="2012-12-31">Werner Wiethege</donor>
   </supporters>
 </donorset>