Get rid of ancient tests that don't work.
Changed Plot derived type to PlotSlice and plotter module to plot.
Initial support for multiple S(a,b) tables. Still need sorting of i_sab_nuclides and i_sab_tables.
Remove assumed short circuit evaluation for S(a,b) tables.
Sort i_sab_nuclides and i_sab_tables. Closes #83.
Some fixes in hdf5_write_materials.
Deallocate names and sab_names in Material derived type.