- shader code migrated from glsl to vulkan-glsl
- #ifdef "Geschnetzel" introduced to support old and rhi graphic APIs
- iotdashboard, shadows examples adjusted
* IOT dashboard: Make light dimmer use arc renderer
* use shadow
* add value text
* add warm and cold parts
* add knob
* handle input
* only move knob when drawing along the arc
* improve input handling
* add tickmarks
* add tickmarks node
* clean up a bit
* Update screenshot of IOT dashboard for github site