Allow plugins to inject additional template-specific open graph tags

[westonruter]

Currently it is not possible to use Jetpack to add og tags for archive templates. This makes it possible to add og tags for them and other templates.

[blobaugh]

Pinging @justinshreve

[blobaugh]

Added to 2.8 milestone. I will test this this week

[westonruter]

Here's some sample code to utilize one of these new filters to add Open Graph meta tags to a category template:

add_filter( 'jetpack_open_graph_base_tags', function ( $meta ) {
    if ( is_category() ) {
        $category = get_queried_object();
        $meta['og:title'] = $category->name;
        $meta['og:url'] = get_category_link( $category->term_id );
        if ( ! empty( $category->description ) ) {
            $meta['og:description'] = $category->description;
        }
    }
    return $meta;
} );