No polarization in `rg1` ?

[giuspugl]

I just realized that rg1 doesn't have polarization. although this goes into the direction of having a low complexity model, i think neglecting the blazar polarization is not realistic. I would propose an rg2 model where we can include the polarization as @xzackli and I did in the websky haloes. polarization is simulated assuming a random pol. angle and pol. frac. 2%( consistent with the latest observations). Is it something easy to include ? can provide a notebook if needed..