Extract FileProvider superclass from EventFilesProvider.

Renamed FileManager to EventFilesProvider.
Adapted tests.
Added comments to supperclass.
Renamed the write method to append.
Pull up getCurrentFilePath

Apparently this method behaves the same for all its subclasses
Added a FileProvider for settings
Added write method to the FileProvider.

Also extracted common method between the write and append method.
Moved the file classes to their own package
Merge branch 'master' into centralFile
Converted inner class to a self contained stub.

The self contained stub can be used to test classes who depend on a real FileProvider.
Extracted stub FileProvider to new file.
Implemented write method in stub
Initial files for properties
Added read method to FileProvider.

Also updated the FileProvider stub
Added the basic functionality for the Properties features.
Test for multiple key insertions added
Removed empty string edge case from the Properties.

It only generated stupidly complex logic for no real benefits.
Added test cases for strange input.
Comments, format, imports
Comments and method reordering
FileProvider subclasses can append their own directory paths to the general root directory.
Created Facade for the Recorder. Created initializer method for the COPEPlugin

With the initializer method, all messy wiring stuff is hidden in the COPEPlugin.
With the Facade, all Recorder internal things are hidden in the Recorder plugin. This prevents exposing internal classes.
Renamed method to sound like the other ones in the class.