Fixed nullrefs in command parsing

src/Discord.Net.Commands/CommandParser.cs

@@ -156,7 +156,7 @@ namespace Discord.Commands
                 return ParseResult.FromError(CommandError.ParseFailed, "A quoted parameter is incomplete");
             
             //Add missing optionals
-            for (int i = paramList.Count; i < command.Parameters.Count; i++)
+            for (int i = argList.Count; i < command.Parameters.Count; i++)
             {
                 var param = command.Parameters[i];
                 if (!param.IsOptional)

src/Discord.Net.Commands/Results/ParseResult.cs

@@ -41,9 +41,13 @@ namespace Discord.Commands
             var argList = new TypeReaderResult[argValues.Count];
             for (int i = 0; i < argValues.Count; i++)
                 argList[i] = TypeReaderResult.FromSuccess(argValues[i]);
-            var paramList = new TypeReaderResult[paramValues.Count];
-            for (int i = 0; i < paramValues.Count; i++)
-                paramList[i] = TypeReaderResult.FromSuccess(paramValues[i]);
+            TypeReaderResult[] paramList = null;
+            if (paramValues != null)
+            {
+                paramList = new TypeReaderResult[paramValues.Count];
+                for (int i = 0; i < paramValues.Count; i++)
+                    paramList[i] = TypeReaderResult.FromSuccess(paramValues[i]);
+            }
             return new ParseResult(argList, paramList, null, null);
         }