Menus: Provide menu settings when creating a new menu.

This simplifies the steps in the process of adding new menus.

Props: garrett-eclipse, audrasjb, ianjvr. 

Built from https://develop.svn.wordpress.org/trunk@48051


git-svn-id: https://core.svn.wordpress.org/trunk@47818 1a063a9b-81f0-0310-95a4-ce76da25c4cd