ctr: add page (#4928)

pages/linux/ctr.md

@@ -0,0 +1,20 @@
+# ctr
+
+> Manage Containerd containers and images.
+> More information: <https://containerd.io>.
+
+- List all containers (running and stopped):
+
+`ctr containers list`
+
+- List all images:
+
+`ctr images list`
+
+- Pull an image:
+
+`ctr images pull {{image}}`
+
+- Tag an image:
+
+`ctr images tag {{souce_image}}:{{source_tag}}  {{target_image}}:{{target_tag}}`