* To play with this you must link your prim before setting it physical, otherwise they won't link in the physics engine properly. This will also be fixed.
* Currently the linked prim are extremely unstable because I have yet to implement combining of forces with the same normal. This will also be fixed. In fact, the whole PhysicsActor, ODEPrim relationship will be reworked to consider groups from the get-go.
* This implementation is better then it crashing your sim, so I'm commiting it for now.
** Added more realistic calculations of mass for the rest of the supported prim shapes+holes+cuts+tapers. Previously they were the generic height * width * length. Spheres roll (Angular velocity) more realistically, etc.
So anyway, it moves the Asset downloading (packet sending) to a module (AssetDownloadModule).
So now at last, AssetCache should be just dealing with fetching assets from the asset server and caching them.
* This might stop some client's constant requests for unfound textures, which is a candidate for the memory leak
* If a texture is not found then the "Image not found" texture will now be displayed clientside
* If it works, this should resolve mantis 676
* Non texture image requests do not receive this packet yet
* This will require a prebuild
* When you select a physical prim, it stops while you've got it selected.
* When you move or alter a prim in some manner, it doesn't become collidable until you de-select it
* When you select a prim, it doesn't become temporarily 'phantom' until you make some change to it while it's selected. (this prevents accidental selections in prim floor from causing it to go phantom on you(but don't move it or you'll fall))
* There's one major difference, and that's a physical object won't stop if you don't have permission to edit it. This prevents people who don't have edit permissions on a prim from stopping it while it's moving.
* Resolve a bad logic bug in AssetCache.GetAsset()
* This may make some asset related things work better (possibly getting main map images will now be improved).
* This should stop the constant increase in the download requests statistics
* If you see stat numbers for download requests which are far from what you'd expect, please report
* This fixes some of the 'runaway downloads' problem but not all of it
* Also fix up logging messages so texture requests are reported as such rather than as assets
* Untangled a tangly shutdown loop for the ScenePresence.
* Suggested to the Garbage Collector that this may be a good time to >.>, <.< *gasp* collect the memory.
* Set the massively slow UpdateEntities method to run every 2 seconds instead of 10 times a second. This method runs through *all* of the entities can calls the virtual update().
* Documented some of the code in the scene.Update method.
* The reason why pending downloads tick ever upwards is because missing assets are never signalled to the TextureSender
* Rectifying this is not straightfoward, but this will constitute the next patch.
* This does not explain the memory leak.
