Switch speed test in README (#640)

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#420 (comment)

README.md

@@ -4,7 +4,7 @@
 
 KaTeX is a fast, easy-to-use JavaScript library for TeX math rendering on the web.
 
- * **Fast:** KaTeX renders its math synchronously and doesn't need to reflow the page. See how it compares to a competitor in [this speed test](http://jsperf.com/katex-vs-mathjax/).
+ * **Fast:** KaTeX renders its math synchronously and doesn't need to reflow the page. See how it compares to a competitor in [this speed test](http://www.intmath.com/cg5/katex-mathjax-comparison.php).
  * **Print quality:** KaTeX’s layout is based on Donald Knuth’s TeX, the gold standard for math typesetting.
  * **Self contained:** KaTeX has no dependencies and can easily be bundled with your website resources.
  * **Server side rendering:** KaTeX produces the same output regardless of browser or environment, so you can pre-render expressions using Node.js and send them as plain HTML.