Install a header which is used indirectly by other headers

diff -rupd libmsn-4.2.orig/msn/CMakeLists.txt libmsn-4.2/msn/CMakeLists.txt
--- libmsn-4.2.orig/msn/CMakeLists.txt	2011-11-19 16:39:10.555916002 +0100
+++ libmsn-4.2/msn/CMakeLists.txt	2011-11-19 16:39:53.047916002 +0100
@@ -38,6 +38,7 @@ set(msn_HEADERS
     passport.h
     sstream_fix.h
     soap.h
+    xmlParser.h
     p2p.h
     msnobject.h
     libmsn_export.h)