Menus: Bring back line break between menu items.

While removing line breaks was great for all use cases except justified menu
items, it broke menus with justified menu items.
Reverts [34321].

Merges [36081] to the 4.4 branch.
Props wp-architect.
Fixes #35107.

Built from https://develop.svn.wordpress.org/branches/4.4@36082


git-svn-id: http://core.svn.wordpress.org/branches/4.4@36047 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/nav-menu-template.php

@@ -211,7 +211,7 @@ class Walker_Nav_Menu extends Walker {
 	 * @param array  $args   An array of arguments. @see wp_nav_menu()
 	 */
 	public function end_el( &$output, $item, $depth = 0, $args = array() ) {
-		$output .= '</li>';
+		$output .= "</li>\n";
 	}
 
 } // Walker_Nav_Menu

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4.1-alpha-36067';
+$wp_version = '4.4.1-alpha-36082';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.