updated input data for solvation plot to match required format for matplotlib contour plot function.

update logic for selecting the orders, so they are not missed if they are not present one of the dicts.

create script for generating plots of the solvation curves, and also output the polynomial fits. Also added unit tests.

created script with methods for generating solvation maps (contour plots) from information read in from files. Added tests for methods that do no produce a plot.

created script and corresponding tests for generating information in the correct format for making a contour plot.

added tests and functions for extraction of fractional occupancy. methods updated so expected results are produced.