Added Expires header and used built in setCacheControl method.
Attempted to set "Cahce-Control: max-age=3600, min-fresh=0" header on
request. However, it does not seem to affect AJAX requests by D3.

Also added MW consumption and date to svg circle elements' title
attribute.
Added "Total Ontario" zone.
I took out transitions. There are too many data points for it to look
smooth and it feels more responsive without them.
Only one log4j2 XML configuration file.