[NTG-context] ConTeXt support in LTEX

Hello, didn't have time to (properly) test, but you might be interested to hear that since 15.2.0 release - hot from the owen - there is now support for ConTeXt as well. Sincerely, Gour -- Bewildered by the modes of material nature, the ignorant fully engage themselves in material activities and become attached. But the wise should not unsettle them, although these duties are inferior due to the performers' lack of knowledge.