CircleCI, CD, Python3, and PipEnv

[diginc]

Circle CI based deployment "Hello World". Dry mode is currently being used while debugging everything. Outstanding questions / To do items

1. Non-prod image destination? Should https://hub.docker.com/r/pihole/pihole/tags be only production builds?
2. Branch filtering ? It'll auto deploy absolutely any branch currently, would just certain prefixes be better? like dev, rc-*, release-*
3. Do tags work for prod releases as expected with this new code. I plan on testing this with dry-run mode still enabled (maybe my diginc/docker-pi-hole fork would be better to test that on to avoid pinging people with fake new releases)

Example output at the end of circle-ci when the deploy script runs:

========================== 35 passed in 21.01 seconds ==========================
Login Succeeded
Using the branch (deploy-images-from-ci) for deployed image version since not passed in
# DEPLOYING:
version: deploy-images-from-ci
branch: deploy-images-from-ci
DRY RUN: echo 
Example tagging: docker tag pihole:armhf pihole/pihole:deploy-images-from-ci_amd64
tox
docker tag pihole:v4.3.2_armhf pihole/pihole:deploy-images-from-ci_armhf
docker push pihole/pihole:deploy-images-from-ci_armhf
docker tag pihole:v4.3.2_amd64 pihole/pihole:deploy-images-from-ci_amd64
docker push pihole/pihole:deploy-images-from-ci_amd64
docker tag pihole:v4.3.2_aarch64 pihole/pihole:deploy-images-from-ci_aarch64
docker push pihole/pihole:deploy-images-from-ci_aarch64
docker manifest create --amend pihole/pihole:deploy-images-from-ci pihole/pihole:deploy-images-from-ci_armhf pihole/pihole:deploy-images-from-ci_amd64 pihole/pihole:deploy-images-from-ci_aarch64
docker manifest annotate pihole/pihole:deploy-images-from-ci pihole/pihole:deploy-images-from-ci_armhf --os linux --arch arm
docker manifest annotate pihole/pihole:deploy-images-from-ci pihole/pihole:deploy-images-from-ci_amd64 --os linux --arch amd64
docker manifest annotate pihole/pihole:deploy-images-from-ci pihole/pihole:deploy-images-from-ci_aarch64 --os linux --arch arm64
docker manifest push pihole/pihole:deploy-images-from-ci

[dschaper]

Left some comment on MM.