Spawn in missing kerbals for kerbal rescue missions instead of skipping them.
Added the expireScreenshot function, which will delete any screenshots that are older than a day, and its checks runs every 10 minutes

Server admins can now change the interval of days to set a screenshot as expired
- Settings now supports double values

Changed ScreenshotExpire to static
Added /version command and added DMP version to mainmenu window title
Removed unused imports