use offer instead of put so that accepting input doesn't block as user may be

able to click on a button multiple times generating multiple calls to
actionClocked

fixes issue 357.

src/magic/ui/GameController.java

@@ -142,11 +142,7 @@ public class GameController {
     }
 
     private void resume(final boolean undoClicked) {
-        try {
-            input.put(undoClicked);
-        } catch (final InterruptedException ex) {
-            throw new RuntimeException(ex);
-        }
+        input.offer(undoClicked);
     }
 
     public void passKeyPressed() {