FS#9487 fixes and improvements of the calendar plugin by Teruaki Kawashima

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@18870 a1c6a512-1295-4272-9138-f99709370657
diff --git a/docs/CREDITS b/docs/CREDITS
index f2244e9..05322d4 100644
--- a/docs/CREDITS
+++ b/docs/CREDITS
@@ -427,6 +427,8 @@
 Francesco Rigoni
 Joël Puik
 Klaas Bosteels
+Teruaki Kawashima
+
 
 The libmad team
 The wavpack team