Neutrino: Channel list: add method isEmpty() and use it, ported from tuxbox cvs (THX Gaucho316)

Origin commit data
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Commit: 35138088e3
Author: Jacek Jendrzej <overx300@gmail.com>
Date: 2012-10-20 (Sat, 20 Oct 2012)

src/gui/channellist.h

@@ -146,6 +146,7 @@ public:
 	int handleMsg(const neutrino_msg_t msg, neutrino_msg_data_t data);
 
 	int getSize() const;
+	bool isEmpty() const;
 	int getSelectedChannelIndex() const;
 	void setSize(int newsize);
 	int doChannelMenu(void);