Create images with no metadata.
Add test images/opengraph/1_simple_200x200.
Change opengraph image:url to absolute URL.

Facebook does not accept relative URLs.
Add test images/opengraph/2_relative_url.
Add test index.
Add tests images/opengraph for size preference.
Sort index alphabetically.
Fix title.
Add test microdata/1_simple.
Add test plain/1_simple.
Update index.