Consolidate and filter get_attached_audio|video|images

[helen]

Seeing as they are so very similar, we should probably just de-spaghetti and consolidate them into get_attached_media( $type ). Should also filter the args and the resulting arrays.

[helen]

In 23776:

Add a generic get_attached_media() function and use it in get_attached_audio|video|images. Add filters for the query args and resulting array. fixes #23843.

[nacin]

So my question is, do we even need the wrapper functions? These aren't template tags, so I'm inclined to think, maybe not.

[wonderboymusic]

I disdain too much reflection, but I like those API funcs. Also, ​http://core.trac.wordpress.org/browser/trunk/wp-includes/post.php#L1701

[DrewAPicture]

In the spirit of reducing the absolute weight of functions we're adding in 3.6 (70+ at last count), I'm with @nacin on ditching the wrapper functions.

[wonderboymusic]

Everyone out of the pool 23843.2.diff​​

[markjaquith]

In 24571:

Drop some wrapper functions

• get_attached_audio() (use get_attached_media( 'audio' ))
• get_attached_images() (use get_attached_media( 'image' ))
• get_attached_videos() (use get_attached_media( 'video' ))

props wonderboymusic. fixes #23843.