Assign sources to types

Requires: main module.

When using configuration providers, Get and Observe method overloads without parameters require an explicit association of the model type with a configuration source.

// This simply won't work (no source defined):

provider.Get<MySettings>();
provider.Observe<MySettings>();

// This will work as expected:

provider.SetupSourceFor<MySettings>(new JsonFileSource("settings.json"));

provider.Get<MySettings>();
provider.Observe<MySettings>();

A source can only be assigned to a type before any Get or Observe calls are made for that type:

provider.SetupSourceFor<MySettings>(source1); // succeeds

provider.SetupSourceFor<MySettings>(source2); // succeeds, overwrites

provider.Get<MySettings>();

provider.SetupSourceFor<MySettings>(source3); // fails