Update SoGo to 2.3.22.

2.3.22 (2017-07-20)
-------------------

New features
- [eas] initial EAS v16 and email drafts support

Enhancements
- [web] updated CKEditor to version 4.7.1

Bug fixes
- [web] use the organizer's alarm by default when accepting IMIP messages (#3934)
- [web] fixed forwarding mails with attachments containing slashes in file names
- [eas] don't include task folders if we hide them in SOGo (#4164)
- [core] not using cleaned data when sending mails (#4199)
- [core] don't update subscriptions when owner is not the active user (#3988)
- [core] enable S/MIME even when using GNU TLS (#4201)
- [core] silence verbose output for sogo-ealarms-notify (#4170)

(taca)