add option to read saved epg data frequently

Origin commit data
------------------
Commit: 6cd5dd8e23
Author: TangoCash <eric@loxat.de>
Date: 2016-11-20 (Sun, 20 Nov 2016)

lib/sectionsdclient/sectionsdMsg.h

@@ -102,6 +102,7 @@ struct sectionsd
 //		std::string network_ntpserver;
 //		std::string epg_dir;
 		int epg_save_frequently;
+		int epg_read_frequently;
 	};
 
 };