Ensure grepping for mounts isn't greedy
Ensure grepping for mounts isn't greedy

pagodabox/nanobox-docker-build,nanobox-io/nanobox-docker-build,nanobox-io/nanobox-docker-build,nanobox-io/nanobox-docker-build,pagodabox/nanobox-docker-build,nanobox-io/nanobox-docker-build