Encode process for loading state level data via a management command

[hectcastro]

When certain types of changes to state level data need to be made, interactions with at least two different storage systems come into play (S3, PostgreSQL). In an effort to make the process more repeatable and safe, attempt to encode the steps necessary in a management command like system. In addition, aim to make the command work in an AWS ECS one-off task setting (minimize local file system use, target /tmp for local file system usage, account for resource constraints in term of CPU and RAM, etc.).

[dmcglone]

We have documented this but would still be better to be scripted.