Wordpres Custom Menu/Navigation Walker - remove all list items from menu, only links remain.

gistfile1.php

//========================================================== CUSTOM MENU WALKER - remove list stuff, only links
class custom_menu_walker_remove_list extends Walker_Nav_Menu {
	function start_el(&$output, $item, $depth, $args) {
		global $wp_query;
		$class_names = $value = '';
		$classes = empty( $item->classes ) ? array() : (array) $item->classes;
		$classes[] = 'menu-item-' . $item->ID;
		$class_names = join( ' ', apply_filters( 'nav_menu_css_class', array_filter( $classes ), $item, $args ) );
		$class_names = ' class="' . esc_attr( $class_names ) . '"';
		$id = apply_filters( 'nav_menu_item_id', 'menu-item-'. $item->ID, $item, $args );
		$id = strlen( $id ) ? ' id="' . esc_attr( $id ) . '"' : '';
		$attributes  = ! empty( $item->attr_title ) ? ' title="'  . esc_attr( $item->attr_title ) .'"' : '';
		$attributes .= ! empty( $item->target )     ? ' target="' . esc_attr( $item->target     ) .'"' : '';
		$attributes .= ! empty( $item->xfn )        ? ' rel="'    . esc_attr( $item->xfn        ) .'"' : '';
		$attributes .= ! empty( $item->url )        ? ' href="'   . esc_attr( $item->url        ) .'"' : '';
		$item_output = $args->before;
		$item_output .= '<a'. $attributes. $id . $class_names .'>';
		$item_output .= $args->link_before . apply_filters( 'the_title', $item->title, $item->ID ) . $args->link_after;
		$item_output .= '</a>';
		$item_output .= $args->after;
		$output .= apply_filters( 'walker_nav_menu_start_el', $item_output, $item, $depth, $args );
	}
	function end_el( &$output, $item, $depth = 0, $args = array() ) {
		$output .= "\n";
	}
}

<p id="main_menu"><?php wp_nav_menu( array('menu' => 'Main Menu', 'container' => '', 'theme_location' => 'primary', 'items_wrap' => '%3$s', 'walker'=> new custom_menu_walker_remove_list() )); ?></p>