Add app for traefik2

Changelog for 0.1.9:

• PR #40 Add Traefik v2 by @alexellis

export KUBECONFIG="$(k3d get-kubeconfig --name='k3s-default')"
k3d create --server-arg "--no-deploy=traefik" --server-arg "--no-deploy=servicelb"

arkade install traefik2

Commits
1bb8afe Add traefik2 app by @braybaut
17fb795 Add Tutorials & community blog posts by @alexellis

Generated by Derek