Added Player handeling

Adding and removing Players is possible now.
Updated States and Basic Playing Feature

Now the Engine is playable. Still some work to do:
	Get the winner in game_over_state
	View/Create Highscore
	Show message if players have the same score
Added View Interface Class

Derive from this to create Views like GUI or CLI
Fixed wrong ID's of the cards

There was a mistake in the shuffle function which is fixed now.
Replaced shuffle function with std::random_shuffle

Now the Id is set by substring of the filename and the whole card array is shuffled using the std::random_shuffle function.
Added functions needed for the User Interface