Merge pull request moby#16091 from sallyom/man-docker-pull

correct man docker-pull

Author: thaJeztah

man/docker-pull.1.md

@@ -14,8 +14,9 @@ NAME[:TAG] | [REGISTRY_HOST[:REGISTRY_PORT]/]NAME[:TAG]
 
 This command pulls down an image or a repository from a registry. If
 there is more than one image for a repository (e.g., fedora) then all
-images for that repository name are pulled down including any tags.
-
+images for that repository name can be pulled down including any tags
+(see the option **-a** or **--all-tags**).
+    
 If you do not specify a `REGISTRY_HOST`, the command uses Docker's public
 registry located at `registry-1.docker.io` by default. 
 
@@ -28,11 +29,11 @@ registry located at `registry-1.docker.io` by default.
 
 # EXAMPLE
 
-# Pull a repository with multiple images
-# Note that if the  image is previously downloaded then the status would be
-# 'Status: Image is up to date for fedora'
+## Pull a repository with multiple images with the -a|--all-tags option set to true.   
+Note that if the  image is previously downloaded then the status would be
+`Status: Image is up to date for fedora`.
 
-    $ docker pull fedora
+    $ docker pull --all-tags fedora
     Pulling repository fedora
     ad57ef8d78d7: Download complete
     105182bb5e8b: Download complete
@@ -48,9 +49,24 @@ registry located at `registry-1.docker.io` by default.
     fedora       heisenbug   105182bb5e8b    5 days ago   372.7 MB
     fedora       latest      105182bb5e8b    5 days ago   372.7 MB
 
-# Pull an image, manually specifying path to Docker's public registry and tag
-# Note that if the  image is previously downloaded then the status would be
-# 'Status: Image is up to date for registry.hub.docker.com/fedora:20'
+## Pull a repository with the -a|--all-tags option set to false (this is the default).
+
+    $ docker pull debian
+    Using default tag: latest
+    latest: Pulling from library/debian
+    2c49f83e0b13: Pull complete 
+    4a5e6db8c069: Pull complete 
+
+    Status: Downloaded newer image for debian:latest
+    
+    $ docker images
+    REPOSITORY   TAG         IMAGE ID        CREATED      VIRTUAL SIZE
+    debian       latest     4a5e6db8c069     5 days ago   125.1 MB
+         
+
+## Pull an image, manually specifying path to Docker's public registry and tag
+Note that if the  image is previously downloaded then the status would be
+`Status: Image is up to date for registry.hub.docker.com/fedora:20`
 
     $ docker pull registry.hub.docker.com/fedora:20
     Pulling repository fedora
@@ -72,3 +88,4 @@ June 2014, updated by Sven Dowideit <[email protected]>
 August 2014, updated by Sven Dowideit <[email protected]>
 April 2015, updated by John Willis <[email protected]>
 April 2015, updated by Mary Anthony for v2 <[email protected]>
+September 2015, updated by Sally O'Malley <[email protected]>