Add ISettingsProvider abstraction to support multiple sources.
Add JSON settings provider.
Add XML settings provider
Convert XML settings provider tests to XUnit.
Configure SimpleSettingsReader directly with an ISettingsProvider
Change the JSON test values to be in the expected key format.
Change XML configuration format to support semicolon separation of keys.
Add loading of configuration file inside simple reader.
Autodetect file type based on extension.
Provide ability to specify file or ISettingsProvider to Autofac module.