Misc UI improvements

[sclaw]

• Regime data entry should refresh when a new gage is loaded.
• inconsistent state refreshing when a new gage is put in the text bar. Sometimes it loads, sometimes it doesn't, sometimes you need to press enter twice.
• Convert any julian days to month labels
• Make the daily mean window view use a date picker widget instead of text
• Add map option to choose gages
• Add rating curve viewer https://waterdata.usgs.gov/nwisweb/get_ratings?site_no=04288000&file_type=exsa (ex. https://streamstats.usgs.gov/ss/?gage=04288000&tab=plots)
• add NWS flood stages (https://api.water.noaa.gov/nwps/v1/gauges/moov1)
• Add data citations