update readme

Author: Dima Kossovich

README.md

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 # How to run
 To start an app do `open ./gui/index.html`, or just open it in your browser manually.
 Check out python and golang samples in a `sample` directory.
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+Timer starts with the first letter starts, max symbols stop is not strict, it works at the end of line (when `<enter>` is pressed).
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+<img src="./sample.png" style="zoom:50%;" />