created planet enum
Revert "created planet enum"

This reverts commit c738c7f6725f8f6132ba63a9f7229ffac978c2e2.
created planet enum
added an planetEvent instance variable that tells when the price will increase. also adjusted getResourcePrice so that it incorporates the new information.
added onTravel method to trigger a random event.
changed random parameter in onTravel method of Planet
added planet instance variable and getter method for planet in mainApplication
Fixes
Show event name in popover.
Add fuel label to dashboard
Add save game button to dashboard
Implement save functionality
Implement load functionality
Handle save / load exceptions.