Fixed the README for DragAndDropMastering sample

ios11/DragAndDropMastering/README.md

@@ -1,4 +1,5 @@
-# Mastering Drag and Drop in iOS 11
+Mastering Drag and Drop in iOS 11
+============
 
 There are two app projects in this sample, intended to be run at the same time on an iPad. The *DragSource* app contains a variety of different types of data for dragging, and the *DragTarget* offers a convenient place to drop them.
 
@@ -6,10 +7,12 @@ There are two app projects in this sample, intended to be run at the same time o
 
 Swift sample available from [WWDC 2017 Mastering Drag and Drop](https://developer.apple.com/videos/play/wwdc2017/213/). See the [original readme](DragAndDropCommon/README.md) for more information.
 
-## License
+License
+-------
 
 Xamarin port changes are released under the MIT license
 
-## Author
+Author
+-------
 
 Ported to Xamarin.iOS by Kevin Mullins, Amy Burns