Fix an internal method BlockingIOProtocol.wait_for() to always raise TimeoutError on timeout for internal use
New connection will now (always) do name resolution, and try all resolved addresses (including IPv6) until succeed
The timeout handling in connect_addr() is also improved, mostly fixing wrong early wraps of TimeoutError (they should be caught and manually handled, re-raising ClientConnectionTimeoutError in the outer BaseConnection.connect())
BlockingIOProtocol.wait_for()to always raiseTimeoutErroron timeout for internal useconnect_addr()is also improved, mostly fixing wrong early wraps ofTimeoutError(they should be caught and manually handled, re-raisingClientConnectionTimeoutErrorin the outerBaseConnection.connect())Refs #491 for the initial IPv6 fix, fixes #486