So Im still relatively new to the MacBook. To watch movies, Ive been hooking up my rMBP to my TV via the HDMI port. How do I allow the movie to play while keeping the lid closed. I looked though the setting and cant seem to find a setting. If possible though, I like to retain the setting for lid closure as it stands now, when not connected. So is there a may to change the behavior only when connected via HDMI?