go/procmgr: implement the actual process manager in C++

refs #7600

Author: Al2Klimov

lib/base/application.cpp

@@ -380,6 +380,7 @@ static void ReloadProcessCallback(const ProcessResult& pr)
 	t.detach();
 }
 
+#ifdef _WIN32
 pid_t Application::StartReloadProcess()
 {
 	// prepare arguments
@@ -413,6 +414,7 @@ pid_t Application::StartReloadProcess()
 
 	return process->GetPID();
 }
+#endif /* _WIN32 */
 
 /**
  * Signals the application to shut down during the next

lib/base/application.hpp

@@ -112,7 +112,9 @@ class Application : public ObjectImpl<Application> {
 
 	void RunEventLoop();
 
+#ifdef _WIN32
 	pid_t StartReloadProcess();
+#endif /* _WIN32 */
 
 	virtual void OnShutdown();