Bug #1108490: fix broken link.

Doc/lib/tkinter.tex

@@ -1353,7 +1353,7 @@ create color images from XPM files.
 
 \item
 \ulink{Compound}
-{http://tix.sourceforge.net/dist/current/man/html/TixCmd/compound.html}
+{http://tix.sourceforge.net/dist/current/man/html/TixCmd/compound.htm}
 image types can be used to create images that consists of multiple
 horizontal lines; each line is composed of a series of items (texts,
 bitmaps, images or spaces) arranged from left to right. For example, a