NASA Challenge_[@dirksavage88]_[Curiosity path model world updates including particle emitter plugin and existing NASA assets (Curiosity path model missing plugins and assets (fixes #19))]

[dirksavage88]

Proposed fix: https://github.com/space-ros/simulation/issues/19

• Add existing NASA mars relevant assets to the curiosity path
• Add particle emitter plugin
• Add basic fog generator model

TODO: get ignition to recognize the .obj files and not just .dae

[mkhansenbot]

I'm not sure if this helps but you might be able to convert from OBJ to DAE