interface: partially fix ipv6 proxy
interface: partially fix ipv6 proxy

note that network.deserialize_proxy is still broken for ipv6

spesmilo/electrum,fujicoin/electrum-fjc,spesmilo/electrum,vialectrum/vialectrum,fujicoin/electrum-fjc,wakiyamap/electrum-mona,fujicoin/electrum-fjc,vialectrum/vialectrum,wakiyamap/electrum-mona,pooler/electrum-ltc,neocogent/electrum,spesmilo/electrum,pooler/electrum-ltc,pooler/electrum-ltc,wakiyamap/electrum-mona,pooler/electrum-ltc,wakiyamap/electrum-mona,vialectrum/vialectrum,spesmilo/electrum,neocogent/electrum,neocogent/electrum