We both love Mary Tyler Moore and look forward to this documentary. Mary Tyler Moore, who lit up the screen with her million-watt smile during the ‘60s and ‘70s, was left nearly in the dark during the final months of her life.    The actress, who starred in “The Dick Van Dyke Show” before charming audiences with her spunk in “The Mary Tyler Moore Show,” was left nearly blind from a decades-long battle with diabetes. She passed away in 2017 at age 80 from a cardiopulmonary arrest after she contracted pneumonia.    The star was diagnosed with Type 1 diabetes at age 33 following a miscarriage. Moore is the subject of a new documentary premiering today on HBO titled “Being Mary Tyler Moore.”