Lose content removal and splitting from the media extraction functions.

see #24484

git-svn-id: http://core.svn.wordpress.org/trunk@24400 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen: remove mention of `twentythirteen_comment()` in PHPDoc, props zeo. Closes #24482.


git-svn-id: http://core.svn.wordpress.org/trunk@24401 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen: Clean up image attachment template and move logic to `twentythirteen_the_attached_image()` function. Props obenland, fixes #24479.


git-svn-id: http://core.svn.wordpress.org/trunk@24402 1a063a9b-81f0-0310-95a4-ce76da25c4cd
POT, generated from r24402

git-svn-id: http://core.svn.wordpress.org/trunk@24403 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen: clean up RTL styles per changes in r24391, see #24469.

git-svn-id: http://core.svn.wordpress.org/trunk@24404 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Twenty Thirteen: correct PHPDoc for using `get_content_url()` to grab first link in post content. See #24469.

git-svn-id: http://core.svn.wordpress.org/trunk@24405 1a063a9b-81f0-0310-95a4-ce76da25c4cd