Propagate ipv6 option to dns lookup function.
Merge pull request #4638 from s0undt3ch/merges/tohojo

Propagate ipv6 option to dns lookup function.
Explicitly disable IPV6 on the test-suite. Should be a No-OP.
Make `salt.payload.SREQ` IPv6 aware.

Since `salt.payload.SREQ` also checks for the `IPV4ONLY` attribute, which was added because of the IPv6 support, and that has proven problematic in some networks, we only set `IPV4ONLY` if IPv6 support is enabled.
Add some logging and print to know what's happening.
`salt.payload.SREQ` should also be able to handle IPv6 addresses.
Fix circular import.