fixed extended handshake error handling to be more robust and fix extension message precedence over plugins
fixed extended handshake error handling to be more robust and fix extension message precedence over plugins

deluge-clone/libtorrent,deluge-clone/libtorrent,deluge-clone/libtorrent,deluge-clone/libtorrent,deluge-clone/libtorrent,deluge-clone/libtorrent