Traefik should get an upgrade to 2.0

[g7morris]

Issue description

Traefik is currently pinned at version 1.7.9.

Given that ISLE 8 is using 2.0+ it would be good to update to a new version from a security and updates standpoint.

It would also give ISLE 7 users another learning area on how to migrate to ISLE 8.

Lastly there are more features in Traefik 2.0 e.g. plugins etc that could extend ISLE 7 positively.

The only drawback is that this would be a breaking change for ISLE users and require a little more documentation.