Move sketch deletion from SketchController into Sketch

This isn't much code, but it makes deletion more consistent with
renaming and saving with the SketchController handling the UI part and
Sketch actually doing the delete.

app/src/processing/app/SketchController.java

@@ -249,20 +249,8 @@ public class SketchController {
                                               options[0]);
     if (result == JOptionPane.YES_OPTION) {
       if (current.isPrimary()) {
-        // need to unset all the modified flags, otherwise tries
-        // to do a save on the handleNew()
-
-        // delete the entire sketch
-        FileUtils.recursiveDelete(sketch.getFolder());
-
-        // get the changes into the sketchbook menu
-        //sketchbook.rebuildMenus();
-
-        // make a new sketch, and i think this will rebuild the sketch menu
-        //editor.handleNewUnchecked();
-        //editor.handleClose2();
+        sketch.delete();
         editor.base.handleClose(editor);
-
       } else {
         // delete the file
         if (!current.deleteFile(BaseNoGui.getBuildFolder(sketch).toPath())) {

arduino-core/src/processing/app/Sketch.java

@@ -332,4 +332,11 @@ public class Sketch {
       FileUtils.copy(getDataFolder(), newDataFolder);
     }
   }
+
+  /**
+   * Deletes this entire sketch from disk.
+   */
+  void delete() {
+    FileUtils.recursiveDelete(folder);
+  }
 }