Merge pull request #5 from jhamrick/develop

Don't set lens on self.cam.node()
Added compound shape to PSO (CPSO).
In CPSO: Added  and  overrides. Bug fixes.
Incremental. CPSO seems to be working.
Added remove_component_bodies() to CPSO
Bug fix
Added warning when you attach a body that has deactivation enabled to the bullet world
added CPSOs to picker.py
bugfix in picker
bugfix
tweak
intermediate commit
Refactoring shape code.
bug fixes
adding unit tests for PSO subclasses, and fixing bugs
tweak
Tweak
tweaked viewer
Add simviewer.py
merge res