(Note: Strong language in the last paragraph) By Susan Heavey WASHINGTON (Reuters) – The United States approved a last-minute flight plan for Venezuelan officials, the State Department said on Friday, after an irate President Nicolas Maduro said his jet was banned from flying over Puerto Rico on his way to China. Washington told Venezuela late on Thursday that permission was granted even though the request had not been properly submitted, State Department spokeswoman Marie Harf said. Maduro said on Twitter at about 10:30 p.m. local time Thursday (11 a.m. …