Updating ManageOwnMedia defaults

Fixes OrchardCMS#5894

Merge branch '1.9.1'

Applying security fix

http://docs.orchardproject.net/Documentation/Patch-20150630

Applying security fix

http://docs.orchardproject.net/Documentation/Patch-20150630

Applying security fix

http://docs.orchardproject.net/Documentation/Patch-20150519

Applying security fix

http://docs.orchardproject.net/Documentation/Patch-20150519

Applying security fix

http://docs.orchardproject.net/Documentation/Patch-20150519

Applying security fix

http://docs.orchardproject.net/Documentation/Patch-20150519

Applying security fix

http://docs.orchardproject.net/Documentation/Patch-20150519

Applying security fix

http://docs.orchardproject.net/Documentation/Patch-20150519