Always create an asset metadata collection in the Mongo modulestore.
If no collection name is specified, use a default name.
https://openedx.atlassian.net/browse/PLAT-294
Consistently name edX branded elements within the LMS [OPEN-300]
Translate "Powered by Open edX" string
Merge pull request #5885 from edx/sarina/name-branded-assets-in-lms

Consistently name branded assets in lms
Merge pull request #5960 from edx/jeskew/default_asset_collection_name

Always create an asset metadata collection in the Mongo modulestore.