(init_server, start_server): Move signal and thread initialization

from init_server() to start_server(), and service startup next to its
Unix equivalent disassoc().  This way, threading is always initialized
after daemonizing, which is simpler and more portable.

src/lib/gen/service.c

@@ -203,7 +203,7 @@ service_ctrl_handler(DWORD Opcode)
 void WINAPI
 service_main(DWORD argc, LPTSTR *argv)
 {
-    init_server(0);
+    init_server();
 
     service_status.dwServiceType        = SERVICE_WIN32; 
     service_status.dwCurrentState       = SERVICE_START_PENDING;