Some updates:
- graphs now scale correctly, the Newbies game doesn't look THAT bad anymore for R'lyeh

- upload mechanism allows fine-tuning of some options now, for example you can set the colors for a specific game era or turn off some graphs if you want
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source code can be inspected, but beware, it's ugly. I put everything into one big file instead of separating it into different PHP files. The core consists of only a couple dozen lines of code since the Javascript code does the real work, the rest is just HTML for the overview/upload pages.