mGuard

Current CK names are based off the producer's certificate. (this is how nac-abe names it), however nac-abe shouldn't have the permission to publish data under ANY stream name, just the specific ones it needs. //CK is an example, as well as //KEY for dkey.

This is a change that either needs to be made in mGuard (giving nac-abe certificates for each data stream) or within nac-abe, depending on its design