New York Theatre Ballet announces the company's 2018-19 performances of their critically acclaimed Once Upon a Ballet series geared to audiences ages 3 and up and running time of one hour for young attention spans. This season's offerings include: Keith Michael's The Nutcracker from December 14-16, 2018 and Cinderella February 9 & 10, 2019 at Florence Gould Hall, 55 E 59th St, New York, NY 10…