Create a softether.upstart file in the Debian overlay for systems that use
the upstart init subsystem. This lets the operator control the SoftEther
daemon with commands like:
# start softether
# stop softether
# status softether
# restart softether
Also modify the softether.init file to exit early if the /etc/init/softether
file is installed. Although the dh_installinit debhelper prefers an upstart
configuration for automatic control, it will also install the sysv script.
