Angular Overview Panels

Summary
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This blueprint will replace the Python overview panels with Angular implementations. The Python panels will be deprecated and the angular views used by default.

Motivation
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The overview panels make a large number of API calls and cause fairly significant slowdown on anything but the smallest of deployments. This has knock-on effects on things like login speed, because it is the default panel shown unless otherwise configured.

Description
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The Project and Admin overview panels will both be replaced with angular views that make asynchronous calls to populate the usage data. The panels should have a more complete view of the available quotas, as well as being significantly faster to load. The load will also not be a blocking load.

UX
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Stylistically similar to the current implementation, but with a tabbed view. This suits the async loading better, and will split up the quotas by project (i.e. Cinder, Nova, Neutron)

Testing
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Standard JS unit testing

Outside Dependencies
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N/A

Requirements Update Required
========================
N/A

Doc Impact
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- A new setting to toggle between the Python and JS Overview panels will be needed
- This will need a release note