Windows: add missing files needed for msi build

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/README b/README
index cc84fed..89a88e9 100644
--- a/README
+++ b/README
@@ -109,9 +109,9 @@
 On Windows Cygwin (http://www.cygwin.com) is required with at least
 devel/gcc4 and devel/make installed in order to build fio, and
 admin/cygrunsrv to run it. You can also install devel/git to fetch/update
-the source files. To create an MSI installer package, install WiX 3.6 from
-http://wix.sourceforge.net/releases/ and run dobuild.cmd from the
-os/windows directory.
+the source files. To create an MSI installer package put a copy of Cygwin
+in os\windows\fio, install WiX 3.6 from http://wix.sourceforge.net/releases/
+and run dobuild.cmd from the os/windows directory.
 
 Before running fio you'll need to have a copy of cygserver running. Run 
 "/usr/bin/cygserver-config" from an elevated Cygwin shell (i.e. launch the