travis: Only deploy once per commit
travis: Only deploy once per commit

Before, we deployed twice for every commit because Travis starts a new
build for each NODEJS_VERSION in the build matrix.

kklin/quilt,kklin/kelda,kklin/quilt,NetSys/quilt,LuiseV/quilt,NetSys/quilt,quilt/quilt,LuiseV/quilt,NetSys/quilt,quilt/quilt,LuiseV/quilt,LuiseV/quilt,kklin/kelda,NetSys/quilt,kklin/quilt,kelda/kelda,kelda/kelda,LuiseV/quilt,kklin/kelda,kklin/quilt,kelda/kelda,quilt/quilt,NetSys/quilt,kelda/kelda,quilt/quilt,kklin/kelda