Change the question at the end of installs and upgrades to present a choice

Change the question at the end of installs and upgrades to present a choice
between exiting to the shell or to reboot the latter being the default.
(On sparc64 the second choice is to halt the system which leaves it at the
OpenBoot PROM prompt)

While there add a newline after the CONGRATULATIONS message.

OK tb@
positive feedback naddy@ deraadt@ giovanni@