skipper: - enable routegroups - fix oidc filters - add absorb() filter for diagnostics
skipper:
- enable routegroups
- fix oidc filters
- add absorb() filter for diagnostics

Signed-off-by: Sandor Szücs <f0c8058f71fcfe5afd63dc9873b61c5120cb7f65@zalando.de>

zalando-incubator/kubernetes-on-aws,zalando-incubator/kubernetes-on-aws,zalando-incubator/kubernetes-on-aws