Make the GUI aware of the new Subordinate info.

After a recent change in juju-core, the subordinate
info is available through the mega-watcher for
services and units. This branch enables the GUI to
fully support this where possible.

Also fixed the code so that uses of "subordinate" vs
"is_subordinate" are consistent.
Add default value to units model subordinate attribute.
Improve the comments reguarding subordinate support in juju-core.
Merge pull request #558 from frankban/subordinate-in-megawatcher

Make the GUI aware of the new Subordinate info.

After a recent change in juju-core, the subordinate
info is available through the mega-watcher for
services and units. This branch enables the GUI to
fully support this where possible.

Also fixed the code so that uses of "subordinate" vs
"is_subordinate" are consistent.
Do not allow scaling up subordinates in machine view.

Also include a few drive by fixes to docstrings.
Added uncommitted status attribute and the method to modify the attribute in the ecs.
Switched machine tokens to use the new commitStatus attribute to indicate the uncommitted/committed UI changes
Container tokens now use the commitStatus property to indicate which status to render
Added css class for the yellow in progress indicator for uncommitted services
Merge pull request #563 from frankban/do-not-scaleup-subordinates

Do not allow scaling up subordinates in machine view.

Also include a few drive by fixes to docstrings.
Sort machine names as numbers where appropriate.
Test that machine names can be sorted as numbers.
Display services as pending deletion.
Add back in latestChange, but more clearly mark it as a notification.
Merge pull request #565 from huwshimi/display-services-as-deleted

Display services as pending deletion

Fixes bug #1370310: display services as pending deletion.
Merge pull request #564 from jaycee/change-notifications

Add back in latestChange, but more clearly mark it as a notification.

`latestChangeDescription` is the piece of data previously provided to the
to the template to make notifications work. Because it wasn't clear it was a notification,
it was incorrectly identified as redundant code and removed. This adds it back in,
with tests, and renames it to make its purpose clearer.
fixed failing tests from commit changed modifications
Fix sort issues when comparing against strings.
Merge pull request #562 from huwshimi/sort-numbers

Sort names by number

Fixes bug #1369794: if machine names are numbers then sort them as numbers.
Fixed the vertical and horizontal alignment of the canvas onboarding.