PhysicsConstraints is documented in the Game Kit Book:
http://download.blender.org/documentation/gamekit1/
VideoTexture is documented in the wiki:
http://wiki.blender.org/index.php/Dev:Source/GameEngine/2.49/VideoTexture
I don't think I will have time to fill the documentation. But I hope this commit helps someone interested in helping it.
Therefore volunteers to document those modules are highly welcome !!! (let's give to BGE the documentation it deserves)!
* + added GameLogic.Lave/LoadGlobalDict + some typo fixes
