* qemud/conf.[ch]: implement parsing and saving network
configs.
* qemud/driver.c: flesh out the stubs
* qemud/internal.h: add networks list etc. to
struct qemud_server
* qemud/qemud.c: add qemudStartNetworkDaemon() and
qemudShutdownNetworkDaemon() stubs.
* qemud/qemud.c: Re-factor out qemudExec() so that it can
be used to launch dnsmasq.
* qemud/conf.c: don't return argc from qemudBuildCommandLine()
as exec() doesn't need it.
