Reduce the flashing in ext_event and identity examples

[futurepaul]

This is pretty hacky, let me know if you have a better idea! My main idea is to move only slightly toward the new random color. The result is the color stays pretty subtle, but I didn't want to introduce more state.

[cmyr]

heh I thought this was just going to turn slow down the timer 😆

[cmyr]

I'm not sure how I feel.

I think it's interesting and I think it looks nicer, but it feels vaguely less illustrative? But then these examples weren't very illustrative, initially.

So... I'm going to say that you should do whatever you want here that feels right, and merge when you're happy.

[fishrockz]

This looks really good, I will go verify, and am happy to approve with the changed function name

[fishrockz]

I get @cmyr 's reservation and I expected a change to just turn the frequency down too. But the effect of this is actually quite nice as you still get the immediate change and you still get a reasonable range of colours, if anything i think the filter could let through slightly higher frequency change.

[futurepaul]

Okay this is a new approach that gets rid of all the old random color logic and just mutates the color randomly. Hits a wider range of colors, still is low on flashing (my primary concern). I'll merge this later today if there are no objections.