Improved "file rescuing" when no file specificion is passed.
* FormatValidation.cs: Abstract class to check if a game file
  matches a format.

* FileContainer.cs: Added tags to store different info like gameCode,
  device, file id...

* Format.cs: IsGuessed property to know that it could be wrong.

* GameFile.cs: Indexer changed to name since path usually is unknown.

* Worker.cs: Added IsGuessed value to format.

* scheme.txt: Removed implemented info.