HA: effect change

[aly-fly]

Just integrated the clock into the HA. Works great.
Annoyance is, that when you want to change the effect, it always sends the pair of two commands ON + Effect.
The ON command flashes displays to black, returns to last display (corrupted), reloads last display and then loads new clock face. And this also takes some time.
I think that when receiving the ON command we should first check if already enabled and skip resetting the existing display.