Added ack to Mateja Jamnik.

--- a/src/Pure/Thy/browser_info.ML	Wed Oct 15 11:16:48 1997 +0200
+++ b/src/Pure/Thy/browser_info.ML	Wed Oct 15 11:27:55 1997 +0200
@@ -3,6 +3,8 @@
     Author:     Stefan Berghofer and Carsten Clasohm
     Copyright   1994, 1997 TU Muenchen
 
+The first design of the text-based html browser is due to Mateja Jamnik.
+
 Functions for generating theory browsing information
 (i.e. *.html and *.graph - files).
 *)