Fix stack status displaying

Add status choices for stacks table.
"Update" status displays correctly now: white field
instead of yellow field and progress bar.

Fixes bug 1207214

Change-Id: I36ca9a41d12a08392e021dcd4ec68642aa07ab12
Enable H201: do not write "except:"

Fixes all occurrences of this. We have a custom exception handler
in Horizon anyway that only catches ClientException in most of these
cases, but this commit lets us gate on the other cases.

Change-Id: Iea3dc13817f3e5b775b2024424bf3a906da5584b
Closes-Bug: #1211657
Fix middleware to not access session fields without user auth

Change-Id: I18bccfa900b25b3ccb1f2514b2c5c0450b54af2d
Fixes: bug #1211535
Adds hypervisor statistics to admin dashboard

Uses the existing d3 visualizations along with the hypervisor
stats API in Nova to display some useful at-a-glance information
about the utilization of your cloud.

Implements blueprint hypervisor-info

Change-Id: If71c533529a1f51d565eafb0b9b84f6ce93427c8
Merge "Enable H201: do not write "except:""
Merge "Adds hypervisor statistics to admin dashboard"
Merge "Fix stack status displaying"
Merge "Fix middleware to not access session fields without user auth"