FT500 explorer

Converting a custom FT500 JSON into FoamTree JSON.
Using the layout option to choose between rectangular and polygonal treemap layouts.
Using the stacking option to enable "flattened" view of the treemap. Using the descriptionGroupSize and descriptionGroupMinHeight options to configure the size of the parent group description fragment depending on the layout.
Using groupLabelLayoutDecorator to draw labels of description groups in bold font.
Using groupColorDecorator to draw groups in custom colors. The color palettes are generated using palette.js.
Using the imageData along with FileSaver.js and base64.js to save the visualization image as a JPEG image.
Using the onGroupHover and onGroupSelectionChanging events to get information about companies being hovered on and selected, so that their details can be presented in the right-hand side panel.