Change link to point to new https website.

Author: HonkingGoose

book/08-customizing-git/sections/attributes.asc

@@ -63,7 +63,7 @@ What is the ``word'' filter?
 You have to set it up.
 Here you'll configure Git to use the `docx2txt` program to convert Word documents into readable text files, which it will then diff properly.
 
-First, you'll need to install `docx2txt`; you can download it from http://docx2txt.sourceforge.net[].
+First, you'll need to install `docx2txt`; you can download it from https://sourceforge.net/projects/docx2txt[].
 Follow the instructions in the `INSTALL` file to put it somewhere your shell can find it.
 Next, you'll write a wrapper script to convert output to the format Git expects.
 Create a file that's somewhere in your path called `docx2txt`, and add these contents: