Correct phpdoc for WP_Query::$post. props lgedeon, fixes #25130.

Built from https://develop.svn.wordpress.org/trunk@25110


git-svn-id: http://core.svn.wordpress.org/trunk@25092 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Have wp-signup.php match the proper default for the 'registration' network option.

props wpmuguru.
fixes #18186.

Built from https://develop.svn.wordpress.org/trunk@25112


git-svn-id: http://core.svn.wordpress.org/trunk@25093 1a063a9b-81f0-0310-95a4-ce76da25c4cd