plot_daily

Bob's advocating for a return to including K600 in the standard plot (which is/used to be `plot_metab_preds`). I agree with the sentiment and have also thought about adding a plot_params() function which would plot parameters (including K600.daily, GPP.daily or Pmax.daily etc. as available).

It might be even better to offer a plot_daily() that allows you to mix and match daily parameters, metabolism predictions, and even values like daily mean Q, temperature, etc.