Added: unlock ticket if owner is away, thanks to Moritz Lenz.
Squashed commit of the following:

commit c633f45c84a0f0ef865b2b77192c929c00f4105a
Author: Moritz Lenz <mlenz@noris.net>
Date:   Fri Mar 7 08:57:00 2014 +0100

    use UnlockOnAway in AgentTicketActionCommon and AgentTicketPhoneCommon

commit 2b778219bc722b0659a7f59f344b773a4d07db32
Author: Moritz Lenz <mlenz@noris.net>
Date:   Thu Mar 6 20:55:13 2014 +0100

    Use Object Manager in Ticket object constructor

    Avoids having two User objects, which could have inconsistent caches,
    and makes the new tests pass.

commit d385cfa067655f689febe9d7e8a2f9cf8346e6d4
Author: Moritz Lenz <mlenz@noris.net>
Date:   Thu Mar 6 20:17:16 2014 +0100

    Unlock Tickets on Article creation if the Owner is out of office

    Adds the backend logic and configuration
Updated AUTHORS.md file.
Removed unneeded RandomID cleanup.
Tidied.
Make test more robust.
Included system dump for system registration feature.
Made test more robust. Sometimes there is no HTTP body returned.
Merge remote-tracking branch 'upstream/master'