Change hx ifconfigwith hx ip address show in documentation

[paaguti]

Expected/Desired Behavior:

One of the samples in README.md should read:
h11 ip address show
(at least for Linux)

Actual Behavior:

Now it reads
h11 ifconfig

Additional Information:

In Linux, ifconfigis deprecated. It is the source of grief for most newbies when they start adding addresses to an interface and ifconfigdoesn't show them.

I know that may mean additional coding in other platforms, but in Networking 101 for Linux we are using the ipcommand only since 2016.

[lantz]

I miss ifconfig – too bad it wasn't maintainer properly on linux distros.

Feel free to submit a pull request.