acks: Add 2 names to ACKNOWLEDGEMENTS file.

ACKNOWLEDGEMENTS

@@ -419,6 +419,7 @@ today.  The names appear in order of pledging.
   868 Stephan Schulte, Germany
   869 Kenneth Henderick
   872 DaveP (www.davepeake.com)
+  873 Markus Schuss, Austria
   876 Kyle Gordon, http://lodge.glasgownet.com
   877 Joseph Gerard Campbell
   881 Thanks for the board. Good luck to you. --Jason Doege
@@ -479,6 +480,7 @@ today.  The names appear in order of pledging.
  1007 Charles V Bock - Charles at CharlesBock dot com
  1010 Remember June 4th, 1989
  1012 Stuart Marsden
+ 1013 Herbert Graef, Stuttgart
  1014 Arthur P, USA
  1015 John Hall & Jeremy Armijo
  1017 Luciano Ramalho, Python.pro.br