Distortion effect in CommonFilters for Panda3D

Distortion effect is useful for simulating heat, e.g. near fires etc., also for water. Would be a good idea to put in CommonFilters.

treeform's fps sample for Panda3D

Add my FPS sample to the samples dir: http://panda3d.org/phpbb2/viewtopic.php?t=4068 Lots of time people ask how to do collisions, fps like mouse or just fps like games. This could be the new "Roaming Ralph" sample as a starting point for most people.

pyro integrated for Panda3D

The pyro system integrated into panda3d + examples on how to use it.