Instance: add method Shutdown()

src/Instance.cxx

@@ -22,6 +22,7 @@
 #include "Partition.hxx"
 #include "Idle.hxx"
 #include "Stats.hxx"
+#include "event/Loop.hxx"
 #include "util/Error.hxx"
 
 #ifdef ENABLE_DATABASE
@@ -32,6 +33,15 @@
 #include "sticker/StickerDatabase.hxx"
 #include "sticker/SongSticker.hxx"
 #endif
+#endif
+
+void
+Instance::Shutdown()
+{
+	event_loop->Break();
+}
+
+#ifdef ENABLE_DATABASE
 
 Database *
 Instance::GetDatabase(Error &error)