Add ability to build docker images for a different Linux distribution

Currently, the build for Impala's docker images builds on the local host OS and then makes the binaries available in the docker build context. The docker image thus needs to run the same Linux distribution and version as the host. Ubuntu 16 docker images should be built on an Ubuntu 16 host. Centos 7 docker images should be built on a Centos 7 host.

It would be useful to be able to build docker containers for a different Linux distribution. Developers often develop on Ubuntu 16, but it would be useful to be able to build Centos 7 docker images to use in other contexts.

To do this, we could build the binaries inside a docker container of a matching version as the docker image we want to produce. This would construct the docker build context, and the binaries would always match. An Ubuntu 16 machine could produce Centos 7 docker containers. Hypothetically, this could also use QEMU to build ARM docker containers on an x86 host.