Sync ping6 output to ping. ping has been around for longer and so

Sync ping6 output to ping. ping has been around for longer and so
defines the canonical output format. Having different output is
getting in the way of a merge.
This moves the output of the src address to the -v option. With the
overly complicated IPv6 address selection it's sometimes usefull to
have this information.
OK benno@, sthen@ can live with it.