Create Chain based on Context

[AdrianStrugala]

New chain implementation, in which all of the methods take context as an input

• output is returned from the final result - or as a separate step
• error handling
• for commands only(?)
• places for implementation: CalculateBestPath, SynchronizePlayer

[AdrianStrugala]

With cancelation token support. Throw on canceled or sth. Add catching TaskCancelledException and return 499

[AdrianStrugala]

this is done I think