This commit adds the following features:
* Ability to expand existing certificate
* Ability to manage object state
* Ability to obtain test certificate
* Ability to promote test certificate to production
* Ability to specify custom certificate name
* Ability to specify multiple domains per certificate
* Ability to use Certbot in standalone mode
* Messaging
This commit also introduces the following behavioral changes:
* Attempt to install Certbot only when it is not installed
already
* Installation of the cron job has to be enabled using
`--automatic-renewal` parameter
**Note:** Object ID is now treated as certificate name and new
required parameter `--domain` was added.