Add sorting option to get_blogs_of_user

[daniloercoli]

The blogs list returned by the function get_blogs_of_user does seem sorted by creation time.

Would be nice to add an optional parameter that can be used to add/modify the sorting behavior.

[nofearinc]

It's worth mentioning that a get_blogs_of_user hook is applied on return:

    return apply_filters( 'get_blogs_of_user', $blogs, $user_id, $all );

[tubiz]

Please can the patch that I added be deleted.
The patch is meant for another ticket.
Thanks

[jeremyfelt]

Duplicate of #15828.