FileProviders: an abstraction for IO and persistency. Recorder Facade. Config file.

Introduced the FileProvider hierarchy. Its sublcasses represent important files to our system, such as event files of config files. Each one can define its own persistency rules (how many files to create, how to switch between them, how to name them, etc)

Introduced the RecorderProperties, the acces point for the plugin config. Eventually it will contain various information such as plugin autoshutdown time.

Introduced a facade for the recorder plugin to be used as an access point to its services and to hide object creation implementation details.