[Icons] [MonoDevelop.Ide] New GTK stock icons replacements:

* copy
* find
* find-and-replace
* go-back
* go-down
* go-forward
* go-up
* home
* jump-to
* media-play
* missing-image
* open
* refresh
* save
* zoom-in
* zoom-out

See https://github.com/xamarin/icons/issues/19

Signed-off-by: Vaclav Vancura <vaclav@vancura.org>