Options:

- client.name.full
- client.name.short
- client.contact.email
- client.contact.phone
- client.website                        URL
- client.website.contact                URL
- client.website.imprint                URL
- client.logo.website                   (optional) true|false

- service.name.full
- service.name.short
- service.meta.description
- service.meta.keywords
- service.website                       URL
- service.maintenance                   (optional) true|false
- service.maintenance.message           (optional)
- service.branding                      (optional) true|false
- service.branding.name
- service.branding.website
- service.login.footer                  (optional) true|false
- service.notify.booking                (optional) true|false

- subject.info                          HTML
- subject.help                          HTML
- subject.type                          (including determiner)
- subject.rules.document.name           (optional)
- subject.rules.document.file           (optional)
- subject.rules.text                    (optional)
- subject.confirmation.text             (optional)

- payment.paypal                        (optional) true|false
- payment.paypal.endpoint               (optional)
- payment.paypal.client.id              (optional)
- payment.paypal.client.secret          (optional)



Bill meta keys:

- payment.method



Booking meta keys:

- notes



Bundle meta keys:

- name



Product meta keys:

- name
- description



Room meta keys:

- name
- info
- description
- pictures



User meta keys:

- gender
- firstname
- lastname
- street
- zip
- city
- country
- phone
- locale                                (optional)
- allow.{privilege}                     (optional) true|false
- deletion.reason                       (optional)
- legacy-pw                             (optional)
- notes                                 (optional)