Create a ephemeral dev container to facilitate testing of
populate_inventory. It can be created, tweeked in the admin interface,
files updated in admin's populate_inventory, then redeployed to deal
with those changes.
A branch based one will need to be created to so we can do this work
without polluting the master branch.
This builds a working docker image for the application.
This is only an initial revision. It needs testing. MySQL, PIL, etc.
Was going to use Alpine, however, python3.6 segfaulted on docker
starting up, and I couldn't find the core files...
