3DS IO add-on: remove 'officially supported' status.

As discussed in T62576, that format is not used much anymore, and we
only have a limited amount of time to dedicate to port and maintain
formats.

Quiet obviously, community is welcomed to take over and port that
add-on as they see fit.

io_scene_3ds/__init__.py

@@ -29,7 +29,6 @@ bl_info = {
     "warning": "",
     "wiki_url": "http://wiki.blender.org/index.php/Extensions:2.6/Py/"
                 "Scripts/Import-Export/Autodesk_3DS",
-    "support": 'OFFICIAL',
     "category": "Import-Export"}
 
 if "bpy" in locals():