Extract plugin interfaces in their own package ?

Writing a go-ipfs plugin at the moment imply to import go-ipfs itself to get the interfaces to implement and expose. This create a circular dependency which, while it works imply to update every plugins for each go-ipfs release otherwise go modules start to mess up the dependencies.

It'd be great if those interfaces could be extracted into their own package/repo to break this cycle.

Now I'm well aware that I dug my own grave with https://github.com/ipfs/go-ipfs/commit/2a9e5005da1ae517f8e4a0aa69bce5a1d752372b as this `PluginDaemonInternal` can't be extracted but it might be the exception to the rule.