Fixes and move to jvmDemo (#286)

orx-shade-styles/src/jvmDemo/kotlin/DemoNPointRadialGradient01.kt

@@ -0,0 +1,41 @@
+import org.openrndr.application
+import org.openrndr.color.ColorRGBa
+import org.openrndr.color.rgb
+import org.openrndr.extensions.SingleScreenshot
+import org.openrndr.extra.shadestyles.NPointRadialGradient
+import org.openrndr.shape.Circle
+import kotlin.random.Random
+
+/**
+ * Demonstrate using a multi color radial gradient.
+ * The gradient has 5 colors (first and last ones are transparent).
+ * Any of the properties can be animated, including colors and points.
+ * See DemoNPointLinearGradient01.kt for an example of animated properties.
+ */
+fun main() {
+    application {
+        program {
+            val gradient = NPointRadialGradient(arrayOf(
+                    ColorRGBa.PINK.opacify(0.0),
+                    ColorRGBa.PINK, ColorRGBa.WHITE, ColorRGBa.PINK,
+                    ColorRGBa.PINK.opacify(0.0)
+            ), arrayOf(0.0, 0.4, 0.5, 0.6, 1.0))
+
+            val circles = List(25) {
+                Circle(Random.nextDouble() * drawer.width,
+                        Random.nextDouble() * drawer.height,
+                        Random.nextDouble() * 150.0)
+            }
+
+            extend {
+                drawer.run {
+                    clear(rgb(0.2))
+                    shadeStyle = gradient
+                    fill = ColorRGBa.WHITE
+                    stroke = null
+                    circles(circles)
+                }
+            }
+        }
+    }
+}