How to make git diff work perfectly with .docx files in Mac OS X (it even colors by word)

instructions.sh

# download docx2txt by Sandeep Kumar
wget -O docx2txt.pl http://www.cs.indiana.edu/~kinzler/home/binp/docx2txt

# make a wrapper 
echo '#!/bin/bash
docx2txt.pl $1 -' > docx2txt
chmod +x docx2txt

# make sure docx2txt.pl and docx2txt are your current PATH. Here's a guide
http://shapeshed.com/using_custom_shell_scripts_on_osx_or_linux/
mv docx2txt docx2txt.pl ~/bin/

# set .gitattributes (unfortunately I don't this can't be set by default, you have to create it for every project)
echo "*.docx diff=word" > .git/info/attributes

# add the following to ~/.gitconfig
[diff "word"]
    binary = true
    textconv = docx2txt

# add a new alias
[alias]
    wdiff = diff --color-words

# try it
git init

# create my_file.docx, add some content

git add my_file.docx

git ci -m "Initial commit"

# change something in my_file.docx

git wdiff my_file.docx

# awesome!

That's "didn't" vs "didn & apos ; t", with no spaces.
The forum software changed my text in the above question!!!
How do I get it to stop comparing & apos ?