Add dev hint line for itss (part of html help).

diff --git a/DEVELOPERS-HINTS b/DEVELOPERS-HINTS
index 78df7e5..7fbe725 100644
--- a/DEVELOPERS-HINTS
+++ b/DEVELOPERS-HINTS
@@ -67,6 +67,7 @@
 	imagehlp/		- PE (Portable Executable) Image Helper lib
 	imm32/			- Input Method Manager
 	iphlpapi/       	- IP Helper API
+	itss/			- Infotech Structured Storage (HTML Help)
 	kernel/			- The Windows kernel
 	lzexpand/		- Lempel-Ziv compression/decompression
 	mapi32/			- Mail interface