Node subver identifies as bcore

[garethtdavies]

zcash-cli getpeerinfo gives the pzec client a subver of bcore e.g.

{
  "id": 84527,
  "addr": "206.189.139.212:46042",
  "addrlocal": "[::159.65.71.195]:8233",
  "services": "0000000000000001",
  "lastsend": 1557844858,
  "lastrecv": 1557844850,
  "bytessent": 2212871574,
  "bytesrecv": 5923029,
  "conntime": 1557113877,
  "timeoffset": 0,
  "pingtime": 0.218735,
  "version": 170007,
  "subver": "bcore",
  "inbound": true,
  "startingheight": 0,
  "banscore": 0,
  "synced_headers": 532051,
  "synced_blocks": 532051,
  "inflight": [],
  "whitelisted": false
}

Presumably, this is a earlier Bitcoin reference that can be updated to be pzec specific? Defined here:

parity-zcash/pzec/main.rs

Line 40 in 5501d46

pub const USER_AGENT: &'static str = "bcore";