Basically the function formerly known as do_main() in main.go has
been renamed launch() and moved into launch.go. Now there are
main.go and main_unix.go files implementing minmial main()
functions which load a config and pass it to launch. This allows
separating unix-specific security stuff (both the actual system
calls which won't compile on other platforms and the definition
of command line switches) out from the platform agnostic
implementation of the main server logic. It also simplifies the
interaction of relative paths in config files with chrooting.
Docs still need updating...
