Add automated/dockerfiles/lts-15.10/Dockerfile
Add automated/dockerfiles/lts-15.10/Dockerfile

For stack-2.3.1

soenkehahn/stackage,fpco/stackage,iand675/stackage,clinty/stackage,michalkonecny/stackage,mrkkrp/stackage,asr/stackage,jonschoning/stackage,massysett/stackage,Daniel-Diaz/stackage,simonmichael/stackage