Fix issue #199 : Always save screenshot with files if new file/file options/save screenshot menu item is enabled (enabled by default)
Screenshots are saved in last format used from "Save Screenshot" menu item (persisted in application settings)
Show error message if screenshot image saving fails
Moved 'use internal GRF parser' option to file/options menu for consistency.


git-svn-id: http://graph-studio-next.googlecode.com/svn/trunk@292 c2f33eb2-41b2-391d-4cb4-d9d0608729ba