VC Speed Dial -- adjust speed by function

Hi,

I needed a small change in the virtual console speed dial properties,
I wanted to adjust speed by function, and also be able to set multipliers on each speed impacted by the speed dial.

With this change, it is possible, with the tap, to change the duration of a function to half-time, and at the same time, another one to two-time.

I find it very helpful for shows !


Documentation update is missing, but I wanted the changes to be reviewed in a first time.
Feel free to comment !