(MAINT) expand on explanation of how `environment-vars` works
(MAINT) expand on explanation of how `environment-vars` works

waynr/puppetserver,briancain/puppet-server,er0ck/puppetserver,briancain/puppet-server,er0ck/puppetserver,rlinehan/puppet-server,rlinehan/puppetserver,erikPrime/puppet-server,puppetlabs/puppetserver,waynr/puppetserver,camlow325/puppet-server,puppetlabs/puppet-server,camlow325/puppetserver,waynr/puppet-server,erikPrime/puppetserver,erikPrime/puppetserver,rlinehan/puppetserver,shrug/puppet-server,puppetlabs/puppet-server,rlinehan/puppet-server,puppetlabs/puppetserver,camlow325/puppet-server,camlow325/puppetserver,camlow325/puppetserver,shrug/puppet-server,waynr/puppetserver,rlinehan/puppet-server,puppetlabs/puppetserver,waynr/puppet-server,er0ck/puppetserver,camlow325/puppet-server,rlinehan/puppetserver,briancain/puppet-server,shrug/puppet-server,camlow325/puppetserver,er0ck/puppetserver,erikPrime/puppet-server,puppetlabs/puppetserver,waynr/puppet-server,erikPrime/puppetserver,rlinehan/puppetserver,erikPrime/puppet-server,shrug/puppet-server,puppetlabs/puppet-server