MILAN (Reuters) -Luxury sports car maker Ferrari said on Wednesday it was improving its forecasts for full-year results, including for core earnings, after beating expectations in the third quarter, supported by a double-digit increase in shipments. The company however struck a more cautious tone on the margin on those core earnings, now seen at around 35% for this year, versus a previous guidance of over 35%. It said industrial costs and research and development expenses weighed for an additional 34 million euros ($33.69 million) on its core result in the past quarter mainly due to higher dep…