tweak comment in Dockerfile
tweak comment in Dockerfile

silberman/Deep-OSM,andrewljohnson/Deep-Trails,andrewljohnson/Deep-Trails,trailbehind/DeepOSM,silberman/Deep-OSM,trailbehind/DeepOSM,andrewljohnson/Deep-Trails,trailbehind/DeepOSM