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.
vInv.clear();
                        }
                    }
                    pto->m_tx_relay->m_last_mempool_req = GetTime<std::chrono::seconds>();
                }
                
                if (fSendTrickle) {
                    
                    std::vector<std::set<uint256>::iterator> vInvTx;
                    vInvTx.reserve(pto->m_tx_relay->setInventoryTxToSend.size());
                    for (std::set<uint256>::iterator it = pto->m_tx_relay->setInventoryTxToSend.begin(); it != pto->m_tx_relay->setInventoryTxToSend.end(); it++) {
                        vInvTx.push_back(it);
                    }
                    CFeeRate filterrate;
                    {
                        LOCK(pto->m_tx_relay->cs_feeFilter);
                        filterrate = CFeeRate(pto->m_tx_relay->minFeeFilter);
                    }
                    
                    
                    CompareInvMempoolOrder compareInvMempoolOrder(&m_mempool, state.m_wtxid_relay);
                    std::make_heap(vInvTx.begin(), vInvTx.end(), compareInvMempoolOrder);
                    
                    
                    unsigned int nRelayedTransactions = 0;
                    LOCK(pto->m_tx_relay->cs_filter);
                    while (!vInvTx.empty() && nRelayedTransactions < INVENTORY_BROADCAST_MAX) {
                        
                        std::pop_heap(vInvTx.begin(), vInvTx.end(), compareInvMempoolOrder);
                        std::set<uint256>::iterator it = vInvTx.back();