Watch for BITCOIND_P2P_HOST for different server than BITCOIND_HOST

Insight will not p2p_sync when *maxconnections* is set in the bitcoind.conf
`{ '0': 'connecting to 127.0.0.1:18333' }`
`{ '0': 'disconnected from peer 127.0.0.1:18333' }`

This issue was discovered troubleshooting random sync issues.