Twenty Fifteen: correct list indentation inside blockquotes.

Props iamtakashi, fixes #30543.



git-svn-id: https://develop.svn.wordpress.org/trunk@30689 602fd350-edb4-49c9-b593-d223f7449a82
Twenty Fifteen: broader selection of avatars that should catch any plugins adding avatars that use the avatar class.

Props iamtakashi, fixes #30541.



git-svn-id: https://develop.svn.wordpress.org/trunk@30690 602fd350-edb4-49c9-b593-d223f7449a82
Improve inline documentation for four methods in `WP_Widget`: `get_field_id()`, `display_callback()`, `update_callback()`, and `form_callback()`.

Props jazzs3quence for the initial patch.
See #30315.


git-svn-id: https://develop.svn.wordpress.org/trunk@30691 602fd350-edb4-49c9-b593-d223f7449a82
Twenty Fifteen: correct stylesheet dependencies.

Props ocean90, fixes #30532.



git-svn-id: https://develop.svn.wordpress.org/trunk@30692 602fd350-edb4-49c9-b593-d223f7449a82