Add a $key_options parameter to apt::key.

If this parameter is defined, in 'apt-key' command string adds --keyserver-options ${key_options} string. This may be useful to work apt-key via proxy.

apt::key { 'puppetlabs':
  key        => '4BD6EC30',
  key_server => 'pgp.mit.edu',
  key_options => "http-proxy=\"http://proxyuser:proxypass@example.org:3128\"",
}

convert to

apt-key adv --keyserver pgp.mit.edu --keyserver-options http-proxy="http://proxyuser:proxypass@example.org:3128" --recv-keys 4BD6EC30

Sorry, but I didn't make spec file, because I don't now how do it. :(