docs-fr | concepts | cluster-administration | logging.md (#15244)

* Add docs/concepts/cluster-administration/logging.md

* Add depending examples

* Translate first 2 chapters

* Coorect the path to debug/counter-pod.yaml

Only the english versions can be directly referenced.

* translate last chapter and adjust to doc style guide

* Fix french ortographic and gramatical errors

* Fix french grammar and orthograph

content/fr/examples/admin/logging/two-files-counter-pod-streaming-sidecar.yaml

@@ -0,0 +1,38 @@
+apiVersion: v1
+kind: Pod
+metadata:
+  name: counter
+spec:
+  containers:
+  - name: count
+    image: busybox
+    args:
+    - /bin/sh
+    - -c
+    - >
+      i=0;
+      while true;
+      do
+        echo "$i: $(date)" >> /var/log/1.log;
+        echo "$(date) INFO $i" >> /var/log/2.log;
+        i=$((i+1));
+        sleep 1;
+      done
+    volumeMounts:
+    - name: varlog
+      mountPath: /var/log
+  - name: count-log-1
+    image: busybox
+    args: [/bin/sh, -c, 'tail -n+1 -f /var/log/1.log']
+    volumeMounts:
+    - name: varlog
+      mountPath: /var/log
+  - name: count-log-2
+    image: busybox
+    args: [/bin/sh, -c, 'tail -n+1 -f /var/log/2.log']
+    volumeMounts:
+    - name: varlog
+      mountPath: /var/log
+  volumes:
+  - name: varlog
+    emptyDir: {}