Introduce save_post_{$post_type} hook.

The hook is fired before the general save_post hook and has the same args as save_post.

props bmb, SergeyBiryukov, ocean90, fixes #16176.
Built from https://develop.svn.wordpress.org/trunk@25050


git-svn-id: http://core.svn.wordpress.org/trunk@25037 1a063a9b-81f0-0310-95a4-ce76da25c4cd
WP_HTTP: Curl: When using Stream-to-file on servers using mbstring.func_overload ensure that the file is written out correctly. Props DrProtocols. See #25061 for trunk

Built from https://develop.svn.wordpress.org/trunk@25051


git-svn-id: http://core.svn.wordpress.org/trunk@25038 1a063a9b-81f0-0310-95a4-ce76da25c4cd