fix(controller): clean up publish_release params

Publishing a release should only know about a source, a dictionary of
configuration, and a target.

Author: Matthew Fisher

controller/registry/mock.py

@@ -1,5 +1,5 @@
 
-def publish_release(src_image, src_tag, config, target_image, target_tag):
+def publish_release(source, config, target):
     """
     Publish a new release as a Docker image
 

controller/registry/private.py

@@ -9,22 +9,24 @@
 from django.conf import settings
 
 
-def publish_release(src_image, src_tag, config, target_image, target_tag):
+def publish_release(source, config, target):
     """
     Publish a new release as a Docker image
 
     Given a source image and dictionary of last-mile configuration,
     create a target Docker image on the registry.
 
     For example publish_release('registry.local:5000/gabrtv/myapp',
-                                '<sha>'
                                 {'ENVVAR': 'values'},
-                                'registry.local:5000/gabrtv/myapp',
-                                'v23',)
+                                'registry.local:5000/gabrtv/myapp',)
     results in a new Docker image at 'registry.local:5000/gabrtv/myapp:v23' which
     contains the new configuration as ENV entries.
     """
     try:
+        src_image = source.rsplit(':', 1)[0]
+        src_tag = source.rsplit(':', 1)[1]
+        target_image = target.rsplit(':', 1)[0]
+        target_tag = target.rsplit(':', 1)[1]
         image_id = _get_tag(src_image, src_tag)
     except RuntimeError:
         if src_tag == 'latest':