Split. From Dusk Till Dawn. Cloverfield. Mama. These are just a few of the horror-tinted titles that opened in January, a month often written off among box-office pundits. But top-tier horror movies and cult-classic flicks have started to chang that stigma in recent years. Enter 2020. Gretel & Hansel, a new approach to a classic fairy tale, will close out January's box office when it opens next weekend. We have an exclusive (and colorful... and creepy) new poster to share with you to celebrate that fact. The poster hails from artist Gary Pullin, who specializes …