VueUiNestedDonuts: added shadow config option:
config.style.chart.layout.donut.useShadow : boolean; // default: false
config.style.chart.layout.donut.shadowColor : string; // default: "#2D353C"
VueUiQuickChart: added shadow config option for donut type:
config.donutUseShadow : boolean; // default: false
config.donutShadowColor : string; // default: "#2D353C"
VueUiXy: when hovering on the chart, line plots radius is now highlighted.