Every winter Mikma and her family travel by foot from their village deep in the Himalayas of Nepal to sell local medicinal plants in urban markets. This year, construction of a new highway to China has begun in their roadless valley, and things are never going to be the same.   The documentary film Baato, distributed by Tull Stories is at once a sensitive portrait of a family that has thus far existed largely apart from the trappings of modernity, a fascinating chronicle of the epic journey they embark on each year, and a penetrating depiction of the culture and politics of Nepal.   The Garden Cinema's Joe Bond talks to co-director Lucas Millard during a satellite Q&A following a screening of the film.