Merge pull request #116 from jread-usgs/master

viz for crop data
Updated python scripts and switched plots to use percent of CA
experiencing severe drought.

Added csv for the data in ca_price_vs_pct_servere_di.csv
Merge remote-tracking branch 'viz_master/master'
minor change to filter
Merge pull request #117 from ayan-usgs/master

Added percentage to CA in severe drought
D3 pie chart for consumptive use
Merge remote-tracking branch 'upstream/master'