Michail Nikolaev

Fix for misleading "Connection is not available, request timed out after" messages

1

Currently ```lastConnectionFailure``` is always used as cause for ```Connection is not available, request timed out after``` exception. But in some cases ```lastConnectionFailure``` could be so old that it become irrelevant....

[Bug]: IPV6-only DNS record are not resolved, but connection by IP works fine

4

**Preconditions** (Any important steps we need to know) Redis cluster with ipv6-only connection. **Steps to reproduce** (How to reproduce what you found step by step) Attempt to connect to it...