Remove unsupported methods from the codebase

[jajik]

These methods are undocummented, without an implementation, and were never used

[rhusar]

The add remove and query I think are from the POC implementation for jgroups discovery. But that has been abandoned and code purged. So I think this is a remnant of that. But I defer to @jfclere

[jfclere]

@rhusar yes those were for some testing of some jgroups stuff. They should be removed now.

[rhusar]

Great, thanks @jfclere and @jajik !