Fitting the Light Curves documentation: Model calculation

[gapp-c]

In the Fitting the Light Curves Documentation, the fit parameters corresponding to each model are given, but the exact meaning of many of the listed parameters is ambiguous since many of them are given in abbreviations only and without units. I think more descriptions of the fit parameters are needed. Also, for the models with analytical expressions (such as model_ramp), I think it'd be useful to state the equation of the model for clarification of the parameters' meanings.

[sebastian-zieba]

For sure. I'll definitely have the units in the next release. For the formulas, I currently link to the python code for each model where the user can check out how it's coded into PACMAN. Having a nice latex-formatted formula there for each model too would be cool for the future.
(duplication of Issue #11)

[sebastian-zieba]

The units and meaning of most parameters are now explained. The formulae can be checked out in the respective python files.