Rework config system

[dninemfive]

Currently, the config system uses a hardcoded KtvConfig class with specific variables for each type of scheduler. This can be reworked to have a generic List<TaskSchedulerConfig<T>> where T : TaskScheduler, loaded with custom code, perhaps with a ConfigNameAttribute to index the various config types.

While i'm at it, might as well switch to using YAML rather than the built-in JSON parser, since i'm writing code in more detail anyway.

This will definitely be intertwined with #8.

[dninemfive]

Come to think of it, having one file containing all of the config is really cumbersome. Each component could be cleanly separated into its own file, with duplicates allowed if multiple of the same component are allowed.

File lookup should be recursive to allow users to group conceptually related config items, but the actual folder structure should not matter, to allow end users to group conceptually related concepts regardless of their actual type.

Ideally, file extensions should be allowed to infer type, with an entry in the YAML to specify component type if necessary.

For example:

(base folder)/
  Work/
    Game.Closer.ktv.yaml
    Discord.Closer.ktv.yaml
    Programming.Closer.ktv.yaml
  Sleep/
    Distractions.Closer.ktv.yaml
  Activities.ktv.yaml
  Categories.ktv.yaml