XML-RPC: Add wp.deleteMediaItem as an alias to wp_deletePost.

props fahmiadib.
fixes #5310.
Built from https://develop.svn.wordpress.org/trunk@28849


git-svn-id: http://core.svn.wordpress.org/trunk@28653 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Slightly bump up the login logo size to avoid getting chopped off by Firefox's rounding problems. props SergeyBiryukov for the initial patch. fixes #28393.

Built from https://develop.svn.wordpress.org/trunk@28850


git-svn-id: http://core.svn.wordpress.org/trunk@28654 1a063a9b-81f0-0310-95a4-ce76da25c4cd