Merge pull request #34 from rhayes-cida/master

Multi-parameter graph.
uncommented EDEN_URL, changed initial date values to use relativedelta
to address missing days in February, added clean methods to forms for a
bit of extra validation
small modification to EDEN_URL and fixed typo in forms.py clean methods
Merge pull request #35 from ayan-usgs/master

minor changes to dates in forms, added clean methods, uncommented EDEN_URL