Fix #676. If a user somehow gets a unparseable (by the 'idna' codec) hostname into the servers list, when it errors on address resolution, it will be rejected in the same was as if it was not found/resolved.  This has a standard server failed to connect handling elsewhere in related systems.
Fix #676. If a user somehow gets a unparseable (by the 'idna' codec) hostname into the servers list, when it errors on address resolution, it will be rejected in the same was as if it was not found/resolved.  This has a standard server failed to connect handling elsewhere in related systems.

fyookball/electrum,fyookball/electrum,fyookball/electrum