Beginning with sprint 13 all commits to rchain/rchain on Github must be signed with a GPG key. The information below provides guidance for getting a GPG key, signing commits locally, and adding your GPG public key to your GitHub account.
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Adding an additional email (commits show up unverified) The email in this signature doesn’t match the committer email.
https://help.github.com/articles/associating-an-email-with-your-gpg-key/
ref https://superuser.com/questions/293184/one-gnupg-pgp-key-pair-two-emails
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