Pad sensitivity fix for Elektron Model:Cycles / Model:Samples

This is a simple and easy to install remedy for numb pads of the Elektron Model:Cycles and Model:Samples grooveboxes. The inserts create a pre-tension between Velostat-coated foil and carbon traces on the PCB, which reduces the amount of force needed to reach the trigger level. It is a follow-up to the Impossibilitron's idea published here: https://www.youtube.com/watch?v=ZSznaM3PfH4.

The tape worked for me, but the resulting sensitivity varied a lot between pads, probably due to accidental folds of the glue layer on the edges of the duct tape, and it was also quite time-consuming to apply. The resistance measured between ground and testpoints TP197 (pad 6) to TP202 (pad 1) in the stock state, unpressed, is around 3.5 MOhm. Using the tape, I got a wide range between 8 and 50 kOhms.

These inserts save a lot of time and lead to a better-controlled result. All pads now measure between 10 and 14 kOhms in my case, and they are a pleasure to play. It may be possible to further fine-tun