Add new toBufferedOutline method to SpritePixels

Add method that returns item image with outline to SpritePixels.

Signed-off-by: Tomas Slusny <slusnucky@gmail.com>

runelite-api/src/main/java/net/runelite/api/SpritePixels.java

@@ -24,6 +24,7 @@
  */
 package net.runelite.api;
 
+import java.awt.Color;
 import java.awt.image.BufferedImage;
 
 /**
@@ -76,4 +77,19 @@ public interface SpritePixels
 	 * @throws IllegalArgumentException if the width or height do not match
  	 */
 	void toBufferedImage(BufferedImage img) throws IllegalArgumentException;
+
+	/**
+	 * Writes the contents of the SpritePixels with chosen outline to the BufferedImage
+	 *
+	 * @param color target color
+	 */
+	BufferedImage toBufferedOutline(Color color);
+
+	/**
+	 * Writes the contents of the SpritePixels with chosen outline to the BufferedImage
+	 *
+	 * @param img target image
+	 * @param color target color
+	 */
+	void toBufferedOutline(BufferedImage img, int color);
 }