Terminology in EID handling is not fully clean
In our current EID handling functions (introduced mainly in !37 (merged)) we refer to the part of a dtn
EID without demux or an ipn
EID with service number zero as "node ID". However, this restriction is not placed by the BP anymore (see explanation by Scott Burleigh). Thus, we should probably use other terminology to refer to the "node ID without service or agent identifier".