Add docs to readme and doc site about container location and availability

[leebrian]

Is this feature for general SeqSender usage or for submitting to a specific database, if so what database?
General usage

Is your feature request related to a problem? If so please describe.
Users are unaware of container locations.

Describe the solution you'd like
Would you please update the readme.md and the docs site with info on where the container is published to github packages and dockerhub, and when.

As a bonus it would be helpful to add flags to the project's readme similar to MIRA to help users understand more about the package availability and which one they should use.

Additional context
This came up after a discussion with tostadas about how to better collaborate and this seems like one of many potential enhancements that are coming up soon.