Merge pull request #6574 from RosettaCommons/roccomoretti/linux_exit
[Foldit] Fix segfaults during Linux shutdown.
I've noticed segfaults when debugging on Linux, and have tracked it down to trying to access various bits of data during program destruction.
Address this by turning off the Server prior to destroying everything, and avoid re-calling the application shutdown code from within the application shutdown procedure.
RELEASE NOTES: Address Segfaults during closing the program on Linux