It is enabled to save screen shot. (Only for DX9)

git-svn-id: https://izanagi.googlecode.com/svn/trunk/@906 05d2ca3c-aac1-175a-b4cf-4be6c0a525a7
Add ScreenShot sample.

git-svn-id: https://izanagi.googlecode.com/svn/trunk/@907 05d2ca3c-aac1-175a-b4cf-4be6c0a525a7