Remove docker/network_automation and docker/python-go-perl-php

[b-ehlers]

These docker images here are outdated, they are maintained at https://github.com/adosztal/gns3-containers.

Since commit 38a58cb from April 2018 the appliances network_automation and python-go-perl-php use the docker images from adosztal.

@adosztal approved this deletion in https://github.com/GNS3/gns3-registry/issues/491#issuecomment-565787325

The containers that I created there can be removed. The appliances are pointing to my repo.

Furthermore I suggest the deletion of the docker images at DockerHub: https://hub.docker.com/r/gns3/network_automation and https://hub.docker.com/r/gns3/python-go-perl-php

[b-ehlers]

@grossmj To have a clean docker repository I suggest to also delete https://hub.docker.com/r/gns3/network_automation and https://hub.docker.com/r/gns3/python-go-perl-php