Converted the inspector header viewlet to a view.
Fixed slot handling in the viewlet manager to support views and viewlets better.
Fixed the rendering of the charm details view.
Adding missing properties to the viewlet base view to support databinding.
Fixed a couple overview test failures
Converted the unit details viewlet into a View
Fixed failing tests from the unit details and inspecter header view conversions
Merge pull request #162 from hatched/header-to-view

To QA
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Do extensive exploratory qa on the inspectors (ghost, service, request series, local charm upgrade, unit details, charm details)

Notes
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- Fixes an issue which broke the local charm request series inspector rendering.
- Contains other drivebys to allow better View rendering