CLuaInstance: Add script function 'channelRezap'

- Alternative rezap method for movie plugins
 - Set Lua api version to 1.21

src/neutrino.h

@@ -234,6 +234,7 @@ public:
 	void screensaver(bool);
 	//signal/event handler before restart of neutrino gui
 	sigc::signal<bool> OnBeforeRestart;
+	void channelRezap();
 };
 #endif