docker multiarch support

[holgerimbery]

Thank you - Michael - for this docker-flow-proxy add-on
please find attached a

PR: add multi architecture support via travis-ci pipeline

• arm64v8, arm32v7 & amd64 images
• manifest :latest with multi architecture support
  (no need to specify architecture during pull)

pipeline needs 4 variables on travis-ci
DOCKER_USERNAME DOCKER_PASSWORD REPO IMAGE_NAME

please check output on docker-hub holgerimbery/docker-flow-letsencrypt for reference

[hamburml]

Thanks! I never used travis-ci before - currently this repository is build via docker hub integration. Let's hope I find some time to learn this.

[holgerimbery]

Michael,

Let's hope I find some time to learn this.
this is pretty simple.

4 steps:

• register a free account on travis-ci.org (with your GitHub Account),
• sync your repros
• configure 4 variables on the settings page for this repro
  DOCKER_USERNAME & DOCKER_PASSWORD will securely store and use your account during the process, both elements will not be visible in logfiles, etc
  REPO := hamburml
  IMAGE_NAME := docker-flow-letsencrypt
• active the repro, and let do travis-ci the rest.

travis-ci will take the code in .travis and build/crossbuild the images, create a manifest and push all the stuff to hub.docker.com

Dockerfile.cross is the template for the Dockerfile,
.travis will push travis-ci in the right direction and
Makefile will take care for the build.