Bug#11754011: 45546: START WINDOWS SERVICE, THEN EXECUTE WHAT IS NEEDED.

Added a global read-only option slow-start-timeout to control the
Windows service control manager's service start timeout, that was
currently hard-coded to be 15 seconds.
The default of the new option is 15 seconds.
The timeout can also be set to 0 (to mean no timeout applicable).

sql/nt_servc.h

@@ -71,6 +71,16 @@ class NTService
     */
     void SetRunning(void);
 
+    /**
+      Sets a timeout after which SCM will abort service startup if SetRunning()
+      was not called or the timeout was not extended with another call to
+      SetSlowStarting(). Should be called when static initialization completes,
+      and the variable initialization part begins
+
+      @arg timeout  the timeout to pass to the SCM (in milliseconds)
+    */
+    void SetSlowStarting(unsigned long timeout);
+
     /*
       Stop() is to be called by the application to stop 
       the service