When I using an alias address like "email@example.com" for gitlab user account,
the generated public key name will "be bob+alias_mydomain_com_1331778284.pub"
but in that case SSHKey#from_file raises error since the regex does not allow to use "+" for account name.
This patch is fix the issue. However, it's better to consider much complex case of an user email .
Add GMail like alias file name support for pub key
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