Fix up based on feedback

Author: gravyboat

user/docker.md

@@ -139,16 +139,16 @@ docker login -e="$DOCKER_EMAIL" -u="$DOCKER_USERNAME" -p="$DOCKER_PASSWORD"
 
 #### Branch Based Registry Pushes
 
-Using `after_success` it is also possible to push an image to a registry based
-on the branch:
+To push a particular branch of your repository to a remote registry,
+use the `after_success` section of your `.travis.yml`:
 
 ```yaml
 
-    after_success:
-      - if [ "$TRAVIS_BRANCH" == "master" ]; then
-          docker login -e="$DOCKER_EMAIL" -u="$DOCKER_USERNAME" -p="$DOCKER_PASSWORD";
-          docker push USER/REPO;
-        fi
+after_success:
+  - if [ "$TRAVIS_BRANCH" == "master" ]; then
+    docker login -e="$DOCKER_EMAIL" -u="$DOCKER_USERNAME" -p="$DOCKER_PASSWORD";
+    docker push USER/REPO;
+    fi
 ```
 
 #### Private Registry Login