Fix #343: handle 'initctl reload' of unmodified non-native services

When 'initctl reload' is called new "configuration generation" is
started by Finit.  This mechanism ensures services reaffirm their
readiness and helps distinguish between their ready before reload
and after.

For native services the pidfile plugin handles this.  The s6 style
services are one-shot only, and thus use a static ready condition.

This patch adds support for stepping the configuration generation
of unmodified systemd style services.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

src/service.h

@@ -49,6 +49,7 @@ void      service_step_all       (int types);
 void      service_worker         (void *unused);
 
 int       service_completed      (void);
+void      service_notify_reconf  (void);
 
 void      service_init           (void);