Add cosmic

Add a tactical change which is already merged into charm-helpers.

This needs to go into all charms to solve the chicken:egg issue
where cosmic is untestable until this change exists.

Reference:

https://github.com/juju/charm-helpers/commit/4835c6c167c429527ef0a0291d17cf559c9cf880

Change-Id: I7c775abf0172bb17e047542c8b1fc728c56bdfe5

hooks/charmhelpers/core/host_factory/ubuntu.py

@@ -21,6 +21,7 @@ UBUNTU_RELEASES = (
     'zesty',
     'artful',
     'bionic',
+    'cosmic',
 )
 
 

tests/charmhelpers/core/host_factory/ubuntu.py

@@ -21,6 +21,7 @@ UBUNTU_RELEASES = (
     'zesty',
     'artful',
     'bionic',
+    'cosmic',
 )