Create Component Documentation

[anthturner]

A lot has changed recently in AuthJanitor, one of the key items being that the architecture is much cleaner and correctly modularized. The upshot is:

• AuthJanitorService rolls up all the requisite integrations, providers, and workflows for processing a secret rotation and sending messages to agents to process a secret rotation
• AuthJanitor.Repository contains AuthJanitorDbContext, which manages the data layer of AuthJanitor, if it is used. This is built on EF, so underlying data store providers will not be AuthJanitor's to maintain anymore, and it allows for really trivial integration to a lot of other consuming platforms (like ASP.NET Core)
• ITokenCredentialProvider is expected to be implemented by the consumer to handle token acquisition callbacks
• AuthJanitor.Automation.AdminApi and AuthJanitor.Automation.AdminUi -- as well as the shared code -- has been completely merged together into a Blazor Server app, which makes development much easier and allows for correctly targeting resources from a local debugger. 🎉

There is a new consumer app, AuthJanitor.CLI which should also be documented. That can be used to run Core and optionally Repository as a non-web client. This should end up being the reference implementation, as it's likely to be a lot simpler than the ASP.NET Core implementation.