🚑 Fix IManager (genericity)

this makes it possible to manipulate the arguments

Sources/Model/IManager.cs

@@ -1,12 +1,12 @@
 using System.Collections.Generic;
 namespace Model
 {
-    internal interface IManager
+    public interface IManager<T>
     {
-        public T Add<T>(ref T toAdd);
-        public void Remove<T>(ref T toRemove);
-        public T Update<T>(ref T before, ref T after);
-        public T GetOneById<T>(int id);
-        public IEnumerable<T> GetAll<T>();
+        public T Add(ref T toAdd);
+        public T GetOneById(int id);
+        public IEnumerable<T> GetAll();
+        public T Update(ref T before, ref T after);
+        public void Remove(ref T toRemove);
     }
 }

Sources/Model/PlayerManager.cs

@@ -6,29 +6,25 @@ using System.Threading.Tasks;
 
 namespace Model
 {
-    internal class PlayerManager : IManager
+    public class PlayerManager : IManager<Player>
     {
-        public T Add<T>(ref T toAdd)
+        public Player Add(ref Player toAdd)
         {
             throw new NotImplementedException();
         }
-
-        public IEnumerable<T> GetAll<T>()
+        public IEnumerable<Player> GetAll()
         {
             throw new NotImplementedException();
         }
-
-        public T GetOneById<T>(int id)
+        public Player GetOneById(int id)
         {
             throw new NotImplementedException();
         }
-
-        public void Remove<T>(ref T toRemove)
+        public void Remove(ref Player toRemove)
         {
             throw new NotImplementedException();
         }
-
-        public T Update<T>(ref T before, ref T after)
+        public Player Update(ref Player before, ref Player after)
         {
             throw new NotImplementedException();
         }