News Interceptor 3 Beta 4

New version of NI3 that includes improvements for settings the news list fonts. Here is the list of updates:

- add: the tray icon now animates when news or feeds are received;
- add: can specify font for both read and unread news;
- add: export feed list to OPML and NIX formats;
- add: option to save logs to file for debugging;
- fix: doesn't remember the font type when restarting the app;
- fix: after hiding the application by minimizing it, the window doesn't show up in in normal size when showing it.