appveyor.yml: Convert from ISO-8859 to UTF-8
diff --git a/appveyor.yml b/appveyor.yml
index 36a4e91..e2ffadb 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -6,7 +6,7 @@
 #                      \___/_/\_\ .__/ \__,_|\__|
 #                               |_| XML parser
 #
-# Copyright (C) 2017 José Gutiérrez de la Concha <jose@zeroc.com>
+# Copyright (C) 2017 José Gutiérrez de la Concha <jose@zeroc.com>
 # Licensed under the MIT license:
 #
 # Permission is  hereby granted,  free of charge,  to any  person obtaining