Covnerted iseoDataSource and weathertablesDataSource to a single
iss4eDataSource so that queries joining the two schema together can be
written efficiently.
Renamed IesoDemandDAO to ZonalDemandSummaryDAO.
All of the pieces are in place for the interactive degree/demand
scatterplot.
Completed the transition between graph elements / categories. 
Zones selection and year selection is currently a list of links on the
left, which will be adjusted later.