Play with maps.
Partial checkin of map.

Starting with a few of mbostock's examples.

Experiments in preparation for map.
Nodes containing circles and text.
Translate nodes instead of their child circles, so that text gets shifted as well.
Better text centering and font. Add credit.
Tweaks to circle size and xpos, to fit it all on-screen.
Color circles with category20c colors.
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# The first commit's message is:
Extend base_minimal.html.

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Add Experiments section to site.

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Experiments section template stuff.

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Put svg into container, for better centering.

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Text tweaks.
First pass at packed bubble layout.
Display city names.
Category 20b colors, number of days, better font size.