get_sale_price

I think a get_sale_price should be added to WC_Product_Woosb class otherwise some components will be getting the wrong sale price from the parent, eg:

//FIX: add sale price so other components using sale price get correct sale price
public function get_sale_price( $context = 'view' ) {
  $product_id = $this->id;
  if ( ( $woosb_price_percent = get_post_meta( $product_id, 'woosb_price_percent', true ) ) && is_numeric( $woosb_price_percent ) && ( intval( $woosb_price_percent ) < 100 ) && ( intval( $woosb_price_percent ) > 0 ) ) {
    return $woosb_price_percent * parent::get_regular_price() / 100;
  }          
  return parent::get_sale_price( $context );
}