Log Message:
Update to 9.0.0

Changelog:
Version 9.0.0 March 8 2016
Major new ownCloud release, more info announcement and upgrading blogs. Summary:

    New: Comments on files
    New: Tags for files
    New: Notifications (separate from Activity feed)
    New: (Federation) Auto-complete of user names
    New: (Federation) Trusted Servers
    New: Code signing, checked when updating or installing core and apps
    New: Stand-alone updater for more reliable upgrading
    Improved sharing behavior and performance
    New External Storage API's for improved scalability
    Calendar and Contacts Apps were rewritten. The CalDAV and CardDAV backends \ 
are now part of core
    Security hardening
    ownCloud API work to improve scalability
    Many small improvements