Add apt::key_options for default apt::key options

[raphink]

This allows to set global default for apt::key options (such as http proxies), just as it is done with keyserver.

[ThoughtCrhyme]

@raphink thanks for the PR! Could you add spec tests for key_options in the same way that we already test keyserver? https://github.com/puppetlabs/puppetlabs-apt/blob/master/spec/unit/puppet/type/apt_key_spec.rb#L20

If we can check that the default setting is undef and test that whatever setting you pass to it properly maintained we can get this merged. Thank you

[raphink]

Thanks for the comment @ThoughtCrhyme . I'm not touching the type though, only the defined resource type, where keyserver defaults is not tested currently. So I'll add tests for both keyserver and key_options.

[raphink]

Looks like the acceptance tests timed out.