Fixes: #10701
Updates the IPv6 documentation and images to reflect the more modern
`ip -6` command set versus `route` and `ifconfig`. Also removes the
use of the special 2002: address range as that is reserved for 6to4
addressing, as well as use of any public address range and re-works the
switched routing example to use 3 subnets of the documentation IPv6
prefix range.
Also conformed all use of addresses to the same doc range per @MalteJ's
commit.
Docker-DCO-1.1-Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com> (github: estesp)
Signed-off-by: Malte Janduda <mail@janduda.net>
