Better server-side plots for 3-series daily data.
View methods for new server-side images.
Server-side 3-series plots integrated to UI.
Automatically choose between single and multi line plots, 
automatically shift to hourly if timespan less than 30 days.
changes to data_views.py
Merge branch 'master' of
https://github.com/rhayes-cida/EDEN-hydrograph-data-rh into
rhayes-cida-master

Conflicts:
	dj_eden_app/hydrograph.py
merged in Roger's changes
Merge pull request #8 from ayan-usgs/master

merged in Roger's changes