remove obsolete methods convolving fiber area using real-space integrals over galsim objects
remove note that shearEllipse is only for visualization

shearEllipse is used for modeling - see ellModel. The code should
probably be revisited since it wasn't super well-tested and the Supri
& Harari model made some approximations. PA, b/a aren't the standard
parameters used for characterizing ellipses in the WL community.