* Remove mysql database connector from container image
See discussion on `dev` mailing list from 2019-03
around [docker
build](http://mail-archives.apache.org/mod_mbox/druid-dev/201903.mbox/browser)
Remove the mysql database connector from the container
image in favour of solely the postgresql connector.
Instructions are present in distribution/docker/README.md
for someone to re-add if they need.
Signed-off-by: Don Bowman <don@agilicus.com>
* Add sample Dockerfile for mysql using pre-built upstream
Don Bowman