Add resolv_timeout to TCPSocket

[mmasaki]

Add resolv_timeout to TCPSocket.new.
It makes DNS timeout customizable in the same way as Socket.tcp.

[mmasaki]

merged in 511fe23

[ioquatix]

Great, this seems like useful feature. However, do you think we should call it resolve_timeout?

[mmasaki]

I intended to make it consistent with Socket.tcp (it accepts resolv_timeout).

[ioquatix]

When was Socket.tcp with resolv_timeout implemented? It seems like poor naming convention.

[mmasaki]

It was in 2019. 0e9d56f
Should we support resolve_timeout instead?

[ioquatix]

I think we should add resolve_timeout including to Socket.tcp and add a deprecation warning for resolv_timeout (it can remain for a while). What do you think?