Attempt to port to IRBuilder

[ibrahimsag]

I have a version of the code with IRBuilder in https://github.com/ibrahimsag/urban-goggles.

I think it is in relatively good shape with some hacks. I would be more then happy to touch the prose to update the tutorial but thought i should give a heads up since there might be another work going on, or the implementation may require adjustment.

Thanks for considering it.

[sdiehl]

Nice, I'll take a look at this and maybe port the tutorial.