Description of problem:
Firstly tag and push image 'openshift/hello-openshift:latest' to docker-registry/project/imagestream1, secondly  tag and push the same image to docker-registry/project/imagestream2, the data could be pushed to docker-registry,but the data shouldn't be pushed   for the second time.

Version-Release number of selected component (if applicable):
openshift v3.3.0.32
kubernetes v1.3.0+52492b4
etcd 2.3.0+git
docker 1.9.1

How reproducible:
Always

Steps to Reproduce:
1. Login OpenShift and create project;
2. Grant registry-admin role to user,  tag and push 'openshift/hello-openshift:latest' to the project;
  `docker tag openshift/hello-openshift:latest docker-registry-default.0926-g15.qe.rhcloud.com/zhouy/hello-openshift:latest`
   `docker push docker-registry-default.0926-g15.qe.rhcloud.com/zhouy/hello-openshift:latest`
3. Tag and push 'openshift/hello-openshift:latest' to the project as another imagestream;
 `docker tag openshift/hello-openshift:latest docker-registry-default.0926-g15.qe.rhcloud.com/zhouy/hello-openshift1:latest`
  `docker push docker-registry-default.0926-g15.qe.rhcloud.com/zhouy/hello-openshift1:latest`

Actual results:
3. The second  time also  push datas to docker-registry;

Expected results:
3. Should prompt the image only mounted from  the previous, don't push datas to docker-registry again.

Additional info:
No issue for docker 1.10