For every peer expose through `getpeerinfo` RPC whether or not we selected them as HB peers, and whether or not they selected us as HB peers.

Suggestion by @gmaxwell.
make_flags = 0;
            }
            for (const CAddress& addr : pto->vAddrToSend)
            {
                if (!pto->m_addr_known->contains(addr.GetKey()))
                {
                    pto->m_addr_known->insert(addr.GetKey());
                    vAddr.push_back(addr);
                    
                    if (vAddr.size() >= MAX_ADDR_TO_SEND)
                    {
                        m_connman.PushMessage(pto, msgMaker.Make(make_flags, msg_type, vAddr));
                        vAddr.clear();
                    }
                }
            }
            pto->vAddrToSend.clear();
            if (!vAddr.empty())
                m_connman.PushMessage(pto, msgMaker.Make(make_flags, msg_type, vAddr));
            
            if (pto->vAddrToSend.capacity() > 40)
                pto->vAddrToSend.shrink_to_fit();
        }
        
        if (pindexBestHeader == nullptr)
            pindexBestHeader = ::ChainActive().Tip();
        bool fFetch = state.fPreferredDownload || (nPreferredDownload == 0 && !pto->fClient && !pto->IsAddrFetchConn()); 
        if (!state.fSyncStarted && !pto->fClient && !fImporting && !fReindex) {
            
            if ((nSyncStarted == 0 && fFetch) || pindexBestHeader->GetBlockTime() > GetAdjustedTime() - 24 * 60 * 60) {