Added helper functions that return the custom description and keywords of the
content as stored in the Add-Meta-Tags or other plugins custom fields.
Added support for reading the description and keywords fields of other similar plugins.
Added support for custom post types.
Added note.
Improved opengraph metadata for image attachment pages.
Fixed minor typo.
Updated copyright notices in the NOTICE file.
Updated info about added metadata in attachment pages.
Set version to 2.1.3 and updated POT file.
Added tag 2.1.3 for changeset 5134b9d2bfd5