Description:
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I configured my Pyrus installation so that it will use a certificate to sign packages I produce.
The problem is, I now have a buildbot using the same user account which builds nightly snapshots of my code as unsigned packages too.
Whenever the slave starts the packaging process, Pyrus prompts it to choose whether the package should be signed or not. Since the slave has no way to answer that prompt, it just sits there, until the timeout for the task is reached, at which point pyrus gets killed.

I know a simple workaround would be to use different user accounts with different Pyrus installations (configurations), but I think it would be valuable to have a command-line option to accept/refuse package signing.

Test script:
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$ pyrus.phar package --sign=no --phar --tgz

Expected result:
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Pyrus should build the phar & tgz archives without prompting the user whether a signature should be used or not.

Actual result:
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Pyrus asks me whether I want a signature to be added or not:

Sign package?
Please choose:
  yes
  no
[yes] :