@param {text[]=} array of upper thresholds; the color according to highest reached threshold is applied (optional)
* @param {color[?](icon0to5,hidden,blank)=icon0} array of colors; 'icon0' through 'icon5' or e. g. '#f00' for red (optional, default = icon0 )
  additionally you can use 'hidden' to not diplay at all or 'blank' to make it invisible but preserve the space that would be used.
  the first one is the base color for values below first threshold, so pass one color more than thresholds.
* @param {text