If you are not Installed fresh after August 26 2017 from the Development Branch
You will have to run an SQL update on your system to enable the feature.
or simply run in your SQL client
ALTER TABLE `Videos` ADD COLUMN `details` TEXT NULL DEFAULT NULL AFTER `status`;
Then you can update your Shinobi to make use of the feature.
If you have the feature already enabled
Setup storage areas in your conf.json file as follows. __DIR__ will automatically be replaced with the running directory of Shinobi.
Once you have modified your conf.json file you must restart Shinobi and refresh any clients for the changes to take effect.