Implement basics for ServiceUnit token/view.
Update new flags to return to li and mv

- Move the deployer bar to the mv flag.
Minor code fixes, per Rick.
Merge pull request #247 from mitechie/update-feature-flags

- Move the deployer bar to the mv flag.
Fix clearing url hash on details close.

- Update the entity-base to pass a null hash in the metadata during the change
event.
- Add tests to both the bundle and charm details that the hash is cleared.

QA
---

Make sure to use the :flags:/il for all QA steps.

 - open a charm details view, go to the readme tab. Verify the url has
   #readme. Close the details and the url should not have any hash any longer.
 - Repeat the process, make sure that you can copy and paste that url with the
   hash into a new browser tab. Then close the details, and the hash goes away.
 - Do the same for bundles.
Fix env header buttons to function.

- Requires the il flag
- Fires correct event updates to show/hide the machine view UI
- Adds a test for the correct events.
- Update to make sure the header is drawn in the new state world.
- Update the CSS to move the machine view panel next to the sidebar.

QA
----

Load the GUI with :flags:/il/mv and click back/forth on the buttons in the
control for Service/Machine views.
Merge pull request #239 from kadams54/deployed-unit-tokens

Right now primarily a code review as this isn't wired into anything yet.
Merge pull request #249 from mitechie/machine-view-control

- Requires the il flag
- Fires correct event updates to show/hide the machine view UI
- Adds a test for the correct events.
- Update to make sure the header is drawn in the new state world.
- Update the CSS to move the machine view panel next to the sidebar.

QA
----

Load the GUI with :flags:/il/mv and click back/forth on the buttons in the
control for Service/Machine views.
Merge pull request #248 from mitechie/closing-details-hash

- Update the entity-base to pass a null hash in the metadata during the change
event.
- Add tests to both the bundle and charm details that the hash is cleared.

QA
---

Make sure to use the :flags:/il for all QA steps.

 - open a charm details view, go to the readme tab. Verify the url has
   #readme. Close the details and the url should not have any hash any longer.
 - Repeat the process, make sure that you can copy and paste that url with the
   hash into a new browser tab. Then close the details, and the hash goes away.
 - Do the same for bundles.
Service inspector closes without flags.
Merge pull request #250 from jaycee/fix-broken-inspector-close

This resolves a simple bug wherein the service inspector (absent flags) would not close after deploying a service; this was simply because the original call to .destroy was no longer made, even without the state flag.

I've not bothered adding tests, as this code will only live for a short while (e.g. the end of this week). In the meantime, we would like comingsoon to still work.

QA
This branch must be QAed against the state flag and without flags. In both cases, after deploying a service, you should be able to close that service's inspector using the close button.
Support tags and root-disk constraints.