gluon-respondd: emit "primary_domain_code" in nodeinfo
Closes #1974
Situation:
==========
$ ls -l /lib/gluon/domains/lindennord.json
lrwxrwxrwx 1 root root 10 Jan 6 03:42 /lib/gluon/domains/lindennord.json -> dom17.json
Before:
=======
$ gluon-neighbour-info -d ::1 -p 1001 -r nodeinfo -c 1
{
"node_id": "525400123456",
"system": {
"domain_code": "lindennord",
"site_code": "ffh"
},
...
}
After:
======
$ gluon-neighbour-info -d ::1 -p 1001 -r nodeinfo -c 1
{
"node_id": "525400123456",
"system": {
"primary_domain_code": "dom17",
"domain_code": "lindennord",
"site_code": "ffh"
},
...
}