Test case for https://github.com/moserware/Skills/issues/7

DrawProbabilityTestCase.cs

using System;
using Moserware.Skills;

class DrawProbabilityTestCase
{
    static void Main()
    {
        var gameInfo = GameInfo.DefaultGameInfo;
        gameInfo.DrawProbability = 0.1;
        
        var player1  = new Player("1",  1.0);
        var player2  = new Player("2",  0.0);
        var player3a = new Player("3a", 1.0);
        var player3b = new Player("3b", 1.0);
        var player4a = new Player("4a", 1.0);
        var player4b = new Player("4b", 0.0);
        
        var team1  = new Team(player1,  gameInfo.DefaultRating);
        var team2  = new Team(player2,  gameInfo.DefaultRating);
        var team3a = new Team(player3a, gameInfo.DefaultRating);
        var team3b = new Team(player3b, gameInfo.DefaultRating);
        var team4a = new Team(player4a, gameInfo.DefaultRating);
        var team4b = new Team(player4b, gameInfo.DefaultRating);
        
        var teams = Teams.Concat(team1, team2, team3a, team3b, team4a, team4b);
        
        Console.WriteLine("Calculating new ratings");
        TrueSkillCalculator.CalculateNewRatings(gameInfo, teams, 1, 2, 3, 3, 4, 4);
        Console.WriteLine("Done");
    }
}