Added default 'num_areas' for data nodes which have zero relations to other areas in InPhO. These nodes no longer disappear when the InPhO button is selected. Introduces a new bug where node circle graphics are the wrong size until removed and readded by the slider. closes #8
now prepending the links to the SVG element to fix redrawing areas
node size now changes in response to button load of data. closes #9
removed second update to boost speed