Allow chasers to run in multiple instances

[enbyted2]

My usecase is along these lines:
- Imagine having a line of 100 RGB pixels
- Imagine having 3 chasers that light up each pixel in sequence in R, G and B (1 chaser for red, 1 for green, 1 for blue)
- Imagine having 6 buttons - 3 that start each chaser (i.e. "shoot" a pixel) and 3 that stop all instances of each chaser

This would allow me to create many different effects with only few buttons.

Now, I know that with current QLC+ structure it would be difficult to implement (since each function is an instance).
I'm hoping for a discussion about such feature. I imagine that it should be implemented for all functions, not just chasers.
This would also make setups with two decks and fading between them easier.

I'd love to get feedback from users that might find such feature useful and if there is enough demand and no hard "No" from Massimo I can look into implementing it into QLC+

[ethanm3]

I would also find this type of layering very useful in my work with RGB matrices!