Add menu_id variable to scss

git-svn-id: https://plugins.svn.wordpress.org/megamenu/trunk@953361 b8457f37-d9ea-0310-8a92-e5e31aec5664
Fix responsive toggle for multiple menus on same page

git-svn-id: https://plugins.svn.wordpress.org/megamenu/trunk@953363 b8457f37-d9ea-0310-8a92-e5e31aec5664