Looking at the php client that someone in the community contributed, it doesn't look compatible with the league filesystem drivers. Their implementation seems very .. outdated.
Because it's not really easy to implement and we also have to keep future maintenance under consideration, I don't think support for this adapter will fall out of thin air.
Maybe you can get someone to commission this as an adapter for upload; but even so I am not in favor of merging this to upload without a much wider adoption. My suggestion would be to use the events available in the extension and local extenders to add the adapter manually.
