Update eog3 to 3.16.2

Highlights from the release notes:

* Install symbolic app icon (Jakub Steiner)
* Improvements to UI changes based on initial feedback (Felix Riemann)
* Adjust UI tests for UI changes (Vadim Rutkovsky)
* More cleanup after the first round of UI modernization
* Make GAction plugin interface actually usable by plugins
  NOTE: Plugins using the old GtkUIManager interface won't work anymore!
* Modernize the GUI (Allan Day, Jente Hidskes, Felix Riemann)
* Migrate to GAction (Jente Hidskes, Felix Riemann)
* Fix preferences dialog when using aggressive linker settings (Felix Riemann)
* Fixed a few memory leaks (Boris Egorov, Felix Riemann)

For full details see:

https://git.gnome.org/browse/eog/tree/NEWS?id=3.16.2

(prlw1)