Dockerfile for CouchDb 1.5.1

[mekane]

Try and find a binary distribution first, then build from source as a last resort. Either way, save the archive to the project to the container can be rebuilt later.

[mekane]

I found an image for CouchDb 1.6.1 and tested it with my script that creates and deletes lots of cycles. It passed the tests and did just fine. I tested up to 150 concurrent creates / deletes. So I think it's fine to proceed with 1.6.1