The `close_main` action should run after `get_template_part( 'loop-nav' )`, not before
Filter the comment form arguments to prevent notice in WordPress 4.1

WordPress 4.1 added two new arguments but Hybrid Core overwrites the
default arguments which caused a PHP notice.
Filter the comment submit class to style it like a button

The button no longer has to have it’s own CSS rules.
Add the post name to the comments title
Small improvement to comment closing logic
Use a <p> tag instead of <h2> for the site description as it's not really a heading
Improve text on 404 error page
Add content-none.php to be used when no posts can be found
Remove unnecessary if statements
Add `download` attribute to the attachment download link

When a user clicks on the link they will be prompted to save it as a
local file instead of being redirected to another page to view the
content in the browser.
Add Hybrid_Media_Meta from Hybrid Core 2.0
Deprecate cakifo_image_info() in favor of hybrid_media_meta()
Use hybrid_media_meta() for image attachments
Update styling and class names for the attachment meta data

* attachment-* instead of image-* as it can be used for more types such
as audio and video.
Don't order the attachment gallery randomly
Better attachment pages

- Meta moved from bottom to the byline
- Removed is_singular() check. Attachment pages are always singular (?)
- Move content above the attachment
- Remove download link as it’s now in the attachment meta
- Show attachment meta using the new Hybrid_Media_Meta class
- Show links to other attachment attached to the same post