Added cross-fade transition to the start button
Added a short (100ms) cross fade transition to the start button (the plus on the start of the header bar)
EDIT: I did this thinking of the transition between the timer "select duration" page and the timer list, but I realized that there is no transition between the AdwViewStack pages (World, Alarm, Stopwatch and Timer), so it might look out of place when it happens there.
Edited by Nokse