fix links

docs/modules/ROOT/pages/jme3/features.adoc

@@ -266,7 +266,7 @@ a|OGG Vorbis music and sounds
 
 == Terrain
 
-*  xref:jme3/advanced/terrain.adoc[Geomipmapped hightmap terrain]
+*  xref:core:terrain/terrain.adoc[Geomipmapped hightmap terrain]
 *  xref:tutorials:how-to/modeling/blender/blender_ogre_compatibility.adoc[Ogre Compatibility]
 *  xref:jme3/advanced/sky.adoc[SkyBox and SkyDome]
 *  Terrain lighting

docs/modules/core/pages/collision/terrain_collision.adoc

@@ -1,7 +1,6 @@
 = terrain_collision
-:author:
-:revnumber:
-:revdate: 2020/07/15
+:revnumber: 2.1
+:revdate: 2020/07/24
 :keywords: terrain, collision
 
 
@@ -284,4 +283,4 @@ You should spawn high up in the area and fall down to the map, giving you a few
 See also:
 
 *  xref:tutorials:beginner/hello_terrain.adoc[Hello Terrain],
-*  xref:jme3/advanced/terrain.adoc[Terrain]
+*  xref:terrain/terrain.adoc[Terrain]

docs/modules/core/pages/scene/control/level_of_detail.adoc

@@ -1,12 +1,12 @@
 = Level of Detail (LOD) Optimization
-:revnumber: 2.0
-:revdate: 2020/07/15
+:revnumber: 2.1
+:revdate: 2020/07/24
 :uri-jme3: https://github.com/jMonkeyEngine/jmonkeyengine/blob/master
 
 
 A mesh with a high level of detail has lots of polygons and looks good close up. But when the mesh is further away (and the detail is not visible), the high-polygon count slows down performance unnecessarily.
 
-One solution for this problem is to use high-detail meshes for objects close to the camera, and low-detail meshes for objects far from the camera. As the player moves through the scene, you must keep replacing close objects by more detailed meshes, and far objects by less detailed meshes. The goal is to keep few high-quality slow-rendering objects in the foreground, and many low-quality fast-rendering objects in the background. (Experienced users can compare this approach to xref:jme3/advanced/terrain.adoc[JME's TerraMonkey terrain system], which internally uses the specialized GeoMipMapping algorithm to generate a terrain's Levels of Detail.)
+One solution for this problem is to use high-detail meshes for objects close to the camera, and low-detail meshes for objects far from the camera. As the player moves through the scene, you must keep replacing close objects by more detailed meshes, and far objects by less detailed meshes. The goal is to keep few high-quality slow-rendering objects in the foreground, and many low-quality fast-rendering objects in the background. (Experienced users can compare this approach to xref:terrain/terrain.adoc[JME's TerraMonkey terrain system], which internally uses the specialized GeoMipMapping algorithm to generate a terrain's Levels of Detail.)
 
 You see now why you may want to be able to generate Levels of Detail for complex Geometries automatically. JME3 supports a Java implementation of the Ogre engine's LOD generator (originally by Péter Szücs and Stan Melax): You use link:{uri-jme3}/jme3-core/src/tools/java/jme3tools/optimize/LodGenerator.java[jme3tools.optimize.LodGenerator] in conjunction with link:{uri-jme3}/jme3-core/src/main/java/com/jme3/scene/control/LodControl.java[com.jme3.scene.control.LodControl].
 
@@ -164,4 +164,4 @@ the lower the quality.
 *  link:https://hub.jmonkeyengine.org/t/brand-new-lod-generator/26341[https://hub.jmonkeyengine.org/t/brand-new-lod-generator/26341]
 *  link:https://github.com/worldforge/ember/tree/master/src/components/ogre/lod[https://github.com/worldforge/ember/tree/master/src/components/ogre/lod]
 *  link:http://www.melax.com/polychop[http://www.melax.com/polychop]
-*  xref:jme3/advanced/terrain.adoc[JME3 TerraMonkey Terrain]
+*  xref:terrain/terrain.adoc[JME3 TerraMonkey Terrain]

docs/modules/tutorials/pages/beginner/hello_terrain.adoc

@@ -1,7 +1,6 @@
 = jMonkeyEngine 3 Tutorial (10) - Hello Terrain
-:author:
-:revnumber:
-:revdate: 2020/07/06
+:revnumber: 2.1
+:revdate: 2020/07/24
 :keywords: beginner, heightmap, documentation, terrain, texture
 :figure-caption!:
 
@@ -414,9 +413,9 @@ Can you combine what you learned here and in xref:beginner/hello_collision.adoc[
 
 == Conclusion
 
-You have learned how to create terrains that are more efficient than loading one giant model. You know how to generate random or create handmade heightmaps. You can add a LOD control to render large terrains faster. You are aware that you can combine what you learned about collision detection to make the terrain solid to a physical player. You are also able to texture a terrain “like a boss using layered Materials and texture splatting. You are aware that the jMonkeyEngine SDK provides a TerrainEditor that helps with most of these manual tasks.
+You have learned how to create terrains that are more efficient than loading one giant model. You know how to generate random or create handmade heightmaps. You can add a LOD control to render large terrains faster. You are aware that you can combine what you learned about collision detection to make the terrain solid to a physical player. You are also able to texture a terrain, like a boss, using layered Materials and texture splatting. You are aware that the jMonkeyEngine SDK provides a TerrainEditor that helps with most of these manual tasks.
 
 *See also:*
 
 *  xref:ROOT:jme3/advanced/terrain_collision.adoc[Terrain Collision]
-*  xref:ROOT:jme3/advanced/terrain.adoc[Advanced Terrain]
+*  xref:core:terrain/terrain.adoc[Advanced Terrain]

docs/modules/tutorials/pages/concepts/faq.adoc

@@ -749,7 +749,7 @@ Use com.jme3.terrain.. The JMonkeyEngine also provides you with a Terrain Editor
 *Learn more:*
 
 * xref:beginner/hello_terrain.adoc[Hello Terrain]
-* xref:ROOT:jme3/advanced/terrain.adoc[Terrain]
+* xref:core:terrain/terrain.adoc[Terrain]
 * xref:sdk:terrain_editor.adoc[Terrain Editor]
 
 *Code sample:*