Map method names to configuration keys automatically (deprecate @ConfKey?)

[A248]

Using @ConfKey to enforce configuration key conventions is brittle and error-prone. I might want to use this-kind-of-format with YAML, and thus use @ConfKey("my-key") on a method name such as "myKey". However, it can be easy to forget this for a single key, which creates a longlasting ugly-looking spot in the configuration.

An interface should be provided to automatically map method names to configuration keys, therefore.

In the same vein of reasoning, we may want to deprecate @ConfKey entirely. I don't see a reason to keep the annotation. Removing it would make reasoning about a config easier for someone who wants to look at their plugin's source code.