Plot multiple models onto fit lightcurve

[tylerbarna]

plotting fits of multiple models for the same analysed data would be a useful visualization tool. This could be accomplished either at time of analysis submission (eg you provide multiple models/priors to light_curve_analysis) or at a later time to generate the lightcurve. This file contains some code for the general idea of implementing multiple models onto one plot, though it would need a bit of work to adapt it into nmma

[sahiljhawar]

For post processing maybe add such tools to a new branch? Also, to plot multiple models, one can now directly use the the data from best fit results #138