change to xrefs

docs/modules/sdk/nav.adoc

@@ -47,14 +47,9 @@
 ***  xref:development/model_loader.adoc[Create a custom model importer]
 ***  xref:increasing_heap_memory.adoc[Increasing Heap Memory]
 ** Available external plugins
-
-*  <<jme3/contributions#,Contributions>>
-*  <<sdk/neotexture#,Neo Texture Editor for procedural textures>>
-*  link:http://www.youtube.com/watch?v=yS9a9o4WzL8[Video: Mesh Tool &amp; Physics Editor]
-*  And more…
-
-
+***  xref:ROOT:jme3/contributions.adoc[Contributions]
+***  xref:neotexture.adoc[Neo Texture Editor for procedural textures]
+***  link:http://www.youtube.com/watch?v=yS9a9o4WzL8[Video: Mesh Tool &amp; Physics Editor]
 ** Development
-
-*  <<sdk/build_platform#,Building jMonkeyEngine SDK>>
-*  <<sdk/development#,Developing plugins for jMonkeyEngine SDK>>
+***  xref:build_platform.adoc[Building jMonkeyEngine SDK]
+***  xref:development.adoc[Developing plugins for jMonkeyEngine SDK]