Breaking Changes
The STAGING and CHICKENEGG env vars were doing the opposite the readme said. The new behaviour is the following:
For STAGING: It will connect to the staging env of let's encrypt if set to 1. If set to 0 or not set it will connect to production env of let's encrypt.
For CHICKENEGG: It will generate a dummy certificate before running the process if set to 1. This there because some http servers won't start without it. Setting it 0 or not setting it all the script expects to already have a certificate. (Will check later if this can be improved in next versions.)