Cleanup tooltip code, use new tooltip system for all visualizations

frontend/src/card/lib/CardRenderer.js

frontend/src/card/lib/tooltip.js

frontend/src/components/Popover.jsx

frontend/src/components/popover/popover.css

frontend/src/components/tooltip/tooltip.css

frontend/src/lib/formatting.js

frontend/src/visualizations/PieChart.jsx

frontend/src/visualizations/TableInteractive.jsx

frontend/src/visualizations/USStateMap.jsx

frontend/src/visualizations/Visualization.jsx

frontend/src/visualizations/WorldMap.jsx

frontend/src/visualizations/components/ChartTooltip.jsx

frontend/src/visualizations/components/LegendHeader.css

frontend/src/visualizations/components/LegendHeader.jsx

frontend/src/visualizations/components/LineAreaBarChart.jsx