[5pt] Misc. upgrades to CatFIM auxiliary tools

[EmilyDeardorff]

The following are upgrades to the CatFIM auxiliary tools that would be nice to have but are not crucial to functioning.

catfim_sites_compare.py:

• add a flag to save a log file and implement logging
• add a flag to save a summary of the differences

catfim_combine_final_outputs.py:

• add a check that the filepath to the newest run name actually exists
• add logic to create_huc_summary_table() that checks whether the sites or lib files exists and factors that into the decision of which outputs to use for a given HUC (and possibly provide the option to toggle this option with the ‘newest run name’ option