Basic android.graphics Rect and Canvas implementation (#461)

Some extensions use more Canvas methods, but they don't
really seem to get that far yet, all the others I was
able to test seem to work now.

AndroidCompat/src/main/java/android/graphics/Canvas.java

@@ -0,0 +1,21 @@
+package android.graphics;
+
+import java.awt.Graphics2D;
+import java.awt.image.BufferedImage;
+import javax.imageio.ImageIO;
+
+public final class Canvas {
+    private BufferedImage canvasImage;
+    private Graphics2D canvas;
+
+    public Canvas(Bitmap bitmap) {
+        canvasImage = bitmap.getImage();
+        canvas = canvasImage.createGraphics();
+    }
+
+    public void drawBitmap(Bitmap sourceBitmap, Rect src, Rect dst, Paint paint) {        
+        BufferedImage sourceImage = sourceBitmap.getImage();
+        BufferedImage sourceImageCropped = sourceImage.getSubimage(src.left, src.top, src.getWidth(), src.getHeight());
+        canvas.drawImage(sourceImageCropped, null, dst.left, dst.top);
+    }
+}