Fix typo in the CRD documentation

[llussy]

I used traefik 2.0, I found When the name contains point，The domain name Can't match.

What does this PR do?

After the test，Traefik fails to match when the name contains point.

when the name contains point.

$ kubectl get ingressroutes.traefik.containo.us whoami.crd -o yaml
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"traefik.containo.us/v1alpha1","kind":"IngressRoute","metadata":{"annotations":{},"name":"whoami.crd","namespace":"kube-system"},"spec":{"entryPoints":["web"],"routes":[{"kind":"Rule","match":"Host(`www.whoami.com`)","priority":12,"services":[{"name":"whoami","port":80}]}]}}
  creationTimestamp: 2019-05-23T05:16:52Z
  generation: 1
  name: whoami.crd
  namespace: kube-system
  resourceVersion: "79805677"
  selfLink: /apis/traefik.containo.us/v1alpha1/namespaces/kube-system/ingressroutes/whoami.crd
  uid: f95540e2-7d19-11e9-b1d0-005056bd0b19
spec:
  entryPoints:
  - web
  routes:
  - kind: Rule
    match: Host(`www.whoami.com`)
    priority: 12
    services:
    - name: whoami
      port: 80

Access to the domain name

$  curl www.whoami.com
404 page not found

log

172.30.50.215 - - [23/May/2019:05:18:36 +0000] "GET / HTTP/1.1" 404 19 "-" "curl/7.54.0" 167 - - 0ms
172.30.50.215 - - [23/May/2019:05:18:37 +0000] "GET / HTTP/1.1" 404 19 "-" "curl/7.54.0" 168 - - 0ms

when the name not contains point.

$ kubectl get ingressroutes.traefik.containo.us whoami.crd 
NAME         AGE
whoami.crd   18m
$ kubectl delete ingressroutes.traefik.containo.us whoami.crd 
ingressroute.traefik.containo.us "whoami.crd" deleted

$ kubectl apply -f whoami.yaml 
ingressroute.traefik.containo.us/whoami created
$ kubectl get ingressroutes.traefik.containo.us --all-namespaces 
NAMESPACE     NAME         AGE
kube-system   whoami       6s
monitoring    promethues   37m
$ kubectl get ingressroutes.traefik.containo.us whoami -o yaml
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"traefik.containo.us/v1alpha1","kind":"IngressRoute","metadata":{"annotations":{},"name":"whoami","namespace":"kube-system"},"spec":{"entryPoints":["web"],"routes":[{"kind":"Rule","match":"Host(`www.whoami.com`)","priority":12,"services":[{"name":"whoami","port":80}]}]}}
  creationTimestamp: 2019-05-23T05:36:09Z
  generation: 1
  name: whoami
  namespace: kube-system
  resourceVersion: "79810408"
  selfLink: /apis/traefik.containo.us/v1alpha1/namespaces/kube-system/ingressroutes/whoami
  uid: ab2a763e-7d1c-11e9-acde-005056bd5fee
spec:
  entryPoints:
  - web
  routes:
  - kind: Rule
    match: Host(`www.whoami.com`)
    priority: 12
    services:
    - name: whoami
      port: 80

Access to the domain name

$  curl www.whoami.com
Hostname: whoami-79f9d7f7d4-qsjqs
IP: 127.0.0.1
IP: 10.244.237.200
GET / HTTP/1.1
Host: www.whoami.com
User-Agent: curl/7.29.0
Accept: */*
Accept-Encoding: gzip
X-Forwarded-For: 10.21.8.24
X-Forwarded-Host: www.whoami.com
X-Forwarded-Port: 80
X-Forwarded-Proto: http
X-Forwarded-Server: traefik-bccd997c6-grtst
X-Real-Ip: 10.21.8.24

log

10.21.8.24 - - [23/May/2019:05:36:59 +0000] "GET / HTTP/1.1" 200 346 "-" "curl/7.29.0" 174 "kubernetescrd.kube-system/whoami-965c93918f12ebd6eb36" "http://10.244.237.200:80" 1ms
10.21.8.24 - - [23/May/2019:05:43:40 +0000] "GET / HTTP/1.1" 200 345 "-" "curl/7.29.0" 175 "kubernetescrd.kube-system/whoami-965c93918f12ebd6eb36" "http://10.244.58.174:80" 1ms

Motivation

update documentation.

More

• Added/updated documentation

[mpl]

@llussy Thank you. As far as I know, the underlying issue is going to be fixed by #4885 (among other things), but since it might take a while to land, it's probably wiser to fix the documentation to reflect the current behaviour that you pointed out. I think there might be a few other places in the documentation that should be fixed similarly, but I'll let @ldez double-check that.

[ldez]

Thanks

[jbdoumenjou]

LGTM