Multiplayer save games from before 1.08 where using the system name as
the password, so they would need to be converted on the original machine
by 1.08-1.09b before they can be transfered to another system.
- Use UiOkDialog() to display all error messages
- Add SDL simple message, and console fallbacks to UiOkDialog()
- Boot graphics early on to facilitate most error messages with build in
gui
- Some more miniwin clean ups