UPDATES:
-------------
* (3/17/09) Added support for Antiportals (thanks Lf3thn4d!), fixed PCZTestApp bug and added example Antiportals.
* (12/19/08) Changed line endings to Windows CR/LF standard in OgreOctreeZone.cpp & OgreDefaultZone.cpp
* (12/19/08) Initial coding for anti-portals has started.  It is not functional yet, so don't use it.
* (12/19/08) Portals no longer cross over other portals if they both lead to the same zone (this was put in to fix a rare bug
  which was causing portals which were "close" to each other to cause inadvertent portal transfers.
* (12/16/08) PCZSceneNode::createChildSceneNode() no longer automatically anchors the new child node if the parent is anchored.  
* (12/16/08) You can un-anchor PCZSceneNodes from Zones by calling PCZSceneNode::anchorToZone(0).
* (12/3/08) Moved this list of updates to it's own file (changelog.txt)
* (12/2/08) Numerous Optimizations (thanks Lf3thn4d) 
 - Update only nodes that moved
 - Update only portals that moved
 - Update nodes that are within interest of moving portals
 - MAJOR CHANGE: Made portal a movable object so that it can track movement
 - Optimized portal update code (Less useless check)
 - Don't clear visiting node each frame but let updating nodes remove themselves from visiting zones File 

* (11/11/08) PCZFrustum treats infinite bounds as always visible and zero bounds as always invisible (Thanks Fish). 
* (10/17/08) PCZoneFactory eats a const String &, so code has been updated to use PCZoneFactory("ZoneType_Default")
  instead of PCZoneFactory (String("ZoneType_Default")).  
* (10/26/08) PCZSM now zeroes out the SkyBoxObj, SkyPlane, and SkyDome pointers when clearScene() is called. 
* (5/8/08) if a scene node is anchored to a zone, then child scene nodes created from that
  scene node (via SceneNode::createChildSceneNode()) are also anchored to the same zone. 
* (4/24/08) Portals can now be closed & opened (see Portal::close() and Portal::open()).
  Closing a portal prevents scene traversal through the portal and also prevents
  scene nodes from crossing the portal. 
* (4/24/08) Infinite Recursion bug for scene traversal FIXED.  This was fixed by adding an
  additional culling plane drawn from the actual plane of quad portals.  The infinite recursion
  bug occurred in situations where a viewer was outside a building, could look straight through
  the building back to the outside, and then into another building similarly set up.  This
  situation is still VERY bad from a performance standpoint, but at least it doesn't crash.  
* (03/18/08) The PCZFrustum now uses a Culling Plane Reservoir which eliminates the constant memory
  allocations/de-allocations for PCPlanes during the culling process. 
* (03/25/08) Light zones now only update affected list when portals move or lights move (Thanks Aulcard)
* (03/25/08) PCZSceneNodes now only save old spatial data when they move (Thanks Aulcard) 