Mcaliley review: runoff notebook comments

In regional_runoff_calculations.ipynb:

• warnings.filterwarnings('ignore') ignores all warnings, not only those from dataretrieval. If you only want to ignore warnings from one package, consider warnings.filterwarnings('ignore', module='dataretrieval') I'm ok with keeping it, but I made a note in the notebook.
• WaterData call crashes ipython, but it works when called in a script from the command line, in a python prompt, in Jupyter, and inside pdb in ipython. Weird! I think this is not a HySwap issue, and may be an ipython bug, not even a pynhd issue. I will make an issue about this, but I don't think I'll investigate further at this time.
• In the Download gage data section, the selected huc is said to be '07090001', but I think it was '17010209'.
• In the Download gage data section, it may help to specify that you're displaying data from one basin (06078500) in the huc just for a quick check (if that is the reason).
• In the Estimate runoff for the huc section, you could link to hyswap's Calculations page.
• In the Estimate runoff for the huc section, isn't df_nwis_ro_data_sub the same as df_year? df_nwis_ro_data_sub seems redundant. Good catch!