restart if the X server connection was lost; since synergy
is likely to be started by xdm or the user's xsession, it's
better for synergy to simply terminate when the connection
is lost. synergy will still restart due to other errors.
also fixed numerous other minor bugs and cleaned some stuff
up (like app error codes are now consistent and enumerated
in Version.h, for lack of a better place). and boosted
version and protocol numbers.
