' fix
icons added as resources (selected from the famfamfam "silk" free icon set); StackPanel added to buttons as "Content" to combine icons with button labels; for now only the Login window and the LotteryChooser window are done (but OK as proof-of-concept)
Merge branch 'nikolas-icons' into mixalis-a2
more icons to buttons!
A bunch of new icons were added to the GUIs (including arrow_refresh.png and user_{add,delete,edit}.png); unused GUI NewCity.xaml{,.cs} was totally removed from the project.