Improved mountpoint metadata manipulation support through /admin calls
Currently we expose this mostly as the old style shoutcast metadata hack requires the data to arrive separate from the stream. This is limited to "title".
We should expose a unified interface that allows updating all mountpoint metadata, including that of the stream/container.
This would make things a lot more flexible and enable new use cases, like adjusting mountpoint information without having to reconnect the source.
Assigned to 2.5.0, pending feasibility checks.