Create endless_terraingrid.adoc

src/docs/asciidoc/jme3/advanced/endless_terraingrid.adoc

@@ -10,7 +10,7 @@ ifdef::env-github,env-browser[:outfilesuffix: .adoc]
 
 [NOTE]
 ====
-Deprecated. Look at link:http://hub.jmonkeyengine.org/forum/topic/design-question-terrain/#post-262072[http://hub.jmonkeyengine.org/forum/topic/design-question-terrain/#post-262072] instead
+Deprecated. Look at link:https://hub.jmonkeyengine.org/t/design-question-terrain/28771[https://hub.jmonkeyengine.org/t/design-question-terrain/28771] instead.
 ====