library: use /proc/version for any non-Linux OS
/proc/sys/kernel/osrelease is quite specific to Linux, and most likely it does not exist on non-Linux OSes that emulate (or are compatible with) the procfs of Linux. OTOH, /proc/version is a bit more generic.
Hence, which the check for using /proc/version from Cygwin to any OS different than Linux.
Signed-off-by: Pino Toscano toscano.pino@tiscali.it