hangman fix? closes #956

src/NadekoBot/Modules/Games/Commands/Hangman/HangmanGame.cs

@@ -52,7 +52,7 @@ namespace NadekoBot.Modules.Games.Commands.Hangman
         }
     }
 
-    public class HangmanGame
+    public class HangmanGame: IDisposable
     {
         private readonly Logger _log;
 
@@ -196,5 +196,11 @@ namespace NadekoBot.Modules.Games.Commands.Hangman
    {(Errors > 1 ? "/" : "  ")} {(Errors > 2 ? "|" : "  ")} {(Errors > 3 ? "\\" : "  ")}       | 
     {(Errors > 4 ? "/" : "  ")} {(Errors > 5 ? "\\" : "  ")}        |
                /-\";
+
+        public void Dispose()
+        {
+            NadekoBot.Client.MessageReceived -= PotentialGuess;
+            OnEnded = null;
+        }
     }
 }

src/NadekoBot/Modules/Games/Commands/HangmanCommands.cs

@@ -52,8 +52,12 @@ namespace NadekoBot.Modules.Games
                 {
                     hm.Start();
                 }
-                catch (Exception ex) {
+                catch (Exception ex)
+                {
                     try { await Context.Channel.SendErrorAsync($"Starting errored: {ex.Message}").ConfigureAwait(false); } catch { }
+                    HangmanGame throwaway;
+                    HangmanGames.TryRemove(Context.Channel.Id, out throwaway);
+                    throwaway.Dispose();
                     return;
                 }