remove the 20 100 default

[jnweiger]

People often claim that most visicut settings are wrong.
This almost always refers to power 20 speed 100 settings, which are visicut defaults.

Change this default to undefined. (or Power 0 speed 0)

[kkaempf]

@jnweiger please be more specific about where these defaults show up.

[jnweiger]

Whenever a material exists, that has no defined settings for this laser, the values 20 / 100 are used.
Define a material for the Zing, switch to the Nova, try to use that material. you get 20 / 100.
We somehow need to detect that no mapping exists for a material and gray out the material or something...

[mgmax]

This has been fixed in the official Visicut version for some time. Feel free to synchronize with upstream :-)