[MCC-140728] Feature/activate deactivate

Adds activate and deactivate methods to the drds controller.  I threw in delete, but that was just for cleanup in specs.  It will be specd out in the next pr.  Also refactored to use bang saves in activate and deactivate methods, and pulled getting the drd from the id param into a helper.  On the testing front, I pulled a bunch of stuff into a MoytaTestHelper module.  Two things Im not particularly happy with are that name, and whether or not I should add accept headers to the helper methods or keep using .hale_json to avoid ambiguity.


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Hmmm... This might be a stupid question... and I apologize in advance if I'm totally off based here...  But is `Roll-e` a valid `kind` value...?  Unless, I'm mistaken, I only see two values available for `kind` in the resource descriptor.  (_See pasted below_).  Thanks very much!

```
      - href: kind
        field_type: select
        options:
          list:
            - standard
            - sentinel
```