Move French index.html for foreword.html

I will then copy the new index.html with the book title.
Copy missing images from English version to French version
Copy new CSS Styles from English version to French version
Add index.html, translated from English to French

I decided to translate the names of HTML pages as well;
while index.html remains the same, I updated the link
to opening.html within to refer to ouverture.html.

My rationale is that the file names appear in the URL
and are displayed in the status bar when hovering links,
and thus they should be meaningful to a French speaker.
Move 'The ' back in title with 'Shape of Design'
Keep markup with English text in comments above French translation
Add 'remix' to the glossary
Translate opening.html to French as ouverture.html