Description

I think that if we have signed PHAR files for PHPMD we can use the same for PHP_Depend. The steps that are needed:

• Finish #521 Sign PHAR builds phpmd/phpmd#688
• Create and publish a key (I suspect @ravage84 need to do this)
• Create a PR to sign the PHAR files.
• Create a PR for https://github.com/phar-io/phar.io/blob/master/data/repositories.xml to add this project to the list.

Checks before submitting

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• This issue is about 1 feature proposal and nothing more.
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