Updating notes based on various tests + notes taken from the reading of
the "Integration web" book
Major update of the test to:
* fix margin in smartphone mode (single column), using box-sizing: border-box;
* old test case (error) stored in a dedicated new file (styles_bug_boites.css)
* add a few things like a pager + menu
Modified to removed bad borders red/yellow
Fixing labels
Responsive navigation added.
Remove absolute positionning for #navigation
Removed header/footer strings as it was messing positionning, will be
replaced by fake content soon