Enable specifying GPG key id in aptly.conf

[swt2c]

It would be helpful if the signing GPG key id could be specified in aptly.conf.

[kisoku]

:+1:

[kisoku]

path to the keyring would also be useful

[jdelic]

I would like to add my vote here. Generally, I'd like to see:

• keyring
• gpgKey
• passphraseFile

as additional options for aptly.conf. Since S3PublishEndpoints can't be specified on the command-line every one of my repos needs a config file anyway (or one larger shared config), so I gain nothing by having to pass half of the necessary parameters through the command-line.

[rrbrussell]

An option to specify the path of the gpg binary would be helpful as well.