GHC 8.2+ and stackage lts-10+ support

[naushadh]

Motivation

We currently use stackage resolver lts-9.21, which ships with GHC-8.0.2. GHC-8.2 has been stable for a while, and GHC-8.4 is about to land.

Besides compiler enhancements, to keep up with newer stackage resolvers/packages, we must support the latest standard stable GHC+stackage-LTS.

Issues

• Official alpine support for GHC-8.2.1 is still pending.
• Official stack support for alpine is still pending.
  • but I don't think this is a blocker as this repo already demonstrates stack support as long as the resolver specific compiler is already installed globally within the builder env. Which means we just need to address the above issue effectively.

[naushadh]

Official alpine support for GHC-8.2.1 is still pending.

One possible workaround for this is to replace the builder's base image with a Debian based OS instead of Alpine. But keep Alpine as the target image so we can still deploy an ultra light container.

Care must be taken to ensure the new builder doesn't drastically explode in size relative to the present/baseline builder.

Inspirations:

• Comment re: multi-stage docker mixing debian's for build and alpine for runtime.
• Issue which mentions the same debian-alpine cross compilation strategy.