* add extra fields settings
* add settings
* add settings link
* allow users to only edit their extra fields
* use nopaging instead of posts_per_page
thanks @mattwiebe
* load filters only on admin page and remove the view actions
* author should not be editable
* some improvements and extra informations
* description
* use nopaging instead
* add blog url
* formatting
* formatting
* some cosmetics
* return attachments
* formatting
* formatting
* add default extra fields
* remove unused migration
* better defaults handling
* use a filter to be able to unhook/replace default extra fields
* should fix#810
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Co-authored-by: Matt Wiebe <wiebe@automattic.com>
