Added a 1.4 tag for tensorflow gpu image

Author: rynge

docker_images.txt

@@ -47,7 +47,8 @@ opensciencegrid/osgvo-ubuntu-xenial
 opensciencegrid/osgvo-blaylockbk
 opensciencegrid/osgvo-torch
 opensciencegrid/tensorflow
-opensciencegrid/tensorflow-gpu
+opensciencegrid/tensorflow-gpu:latest
+opensciencegrid/tensorflow-gpu:1.4
 rynge/einsteintoolkit:latest
 rynge/osg-tensorflow-gpu:latest
 rynge/osgvo-el6-testing:latest