A website that turns .hgignore to .gitignore. Mercurial Ignore File ---> Git
You can:
Either paste the .hgignore text into the text box and then copy the result.
Or upload a .hgignore file. Then you will be prompted to download a .gitignore file.
The .gitignore file will be named "_.gitignore" because webbrowsers see filenames that are only extensions as malicious.