Addition of hindi caption

Hello Sameer,

Thank you for writing in with your request. As we are going through our community archive, we feel humbled and encouraged by the many requests for an expansion of the Hindi language content. That said, I've passed this feedback along to the appropriate team. As we grow and expand, we’re continuing to add new languages to offer a better education at Khan Academy. Investing more heavily in the language team is very important to us

All the best,

Alex