Logging: TerminalPublisher, update PHPDocs.
Logging: Extending CoreObject, filterable.
Logging: CompoundPublisher refactoring.
Logger: DefaultLogger, refactoring, moving filtering to parent class.
Logging: BaseTransformer, refactored configuration out to CoreObject.
Logging: AbstractFilter, first implementation.
Logging: LogLevel, update check method.
Logging: AbstractLogger, extends CoreObject.