Media: Don't add menu_order to newly uploaded attachments, to match 3.4...

Media: Don't add menu_order to newly uploaded attachments, to match 3.4 behavior. Reverts a bit of [22967]. props koopersmith. fixes #22607.



git-svn-id: https://core.svn.wordpress.org/trunk@22985 1a063a9b-81f0-0310-95a4-ce76da25c4cd