Use a more light weight base image

[csantanapr]

Currently using ubuntu base image FROM ibmcom/ubuntu:14.04
We should use instead a more light way image like official golang images golang:1.10.1

[sciabarra]

We can even use just a plain ubuntu for the base image. I could use even alpine but binaries need a libc generally so I would like to have it in the image, so I would opt for ubuntu

[csantanapr]

I preferred ubuntu