remove gaps

docs/modules/sdk/nav.adoc

@@ -3,9 +3,7 @@
 *** SDK Use Case Tutorials
 ****  link:http://www.youtube.com/watch?v=-OzRZscLlHY[Video: jMonkeyEngine SDK Use Case Demo 1 (Quixote demo)]
 ****  link:http://www.youtube.com/watch?v=6-YWxD3JByE[Video: jMonkeyEngine SDK Use Case Demo 2 (Models and Materials)]
-
 *** SDK Tutorials
-
 ****  link:http://www.youtube.com/watch?v=M1_0pbeyJzI[Video: jMonkeyEngine SDK - Basics]
 ****  link:http://www.youtube.com/watch?v=nL7woH40i5c[Video: jMonkeyEngine SDK - Importing Models]
 ****  link:http://www.youtube.com/watch?v=DUmgAjiNzhY[Video: jMonkeyEngine SDK - Dragging&Dropping Nodes]