Add pagination support to the volume page in the Dashboard

[Roman Rufanov]

The cinder V2 API supports pagination, however, the dashboard volume page does not currently leverage the support. Without this support the listing of more than a 100 volumes takes a long time. This is really painful and should be fixed.
Customer has 200+ volumes and it takes 48+ seconds. Need to paginate and cache information for faster retrial and display.

[Roman Rufanov (rrufanov)]

Customer found on MODS 6.0 . It takes over 48 seconds to list 200 volumes. Need fix.

[Vitaly Sedelnik (vsedelnik)]

The described behavior is expected for older versions, this is not a bug but feature request.

Confirmed and assigned to Horizon team for 8.0.
Setting as Won't Fix for 6.0, 6.1 and 7.0.

Horizon team - please comment whether some workaround is available for this issue? Is it possible to improve customer experience by enabling caching or in some other way?

[Timur Sufiev (tsufiev-x)]

A big amount of volumes is not the single cause of 48+ seconds response delay. Another issue that contributes a significant delay is https://bugs.launchpad.net/mos/+bug/1508427 Once we fix redundant Nova calls at Admin->Volumes page, response delay should decrease.

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/13099
Submitter: Pkgs Jenkins <email address hidden>
Branch: openstack-ci/fuel-8.0/liberty

Commit: 7ed7535a46007218d33f68bcbbfbf36cf02d6c47
Author: Mingyan Bao <email address hidden>
Date: Wed Nov 25 11:04:30 2015

Add pagination support to the volume page

Cinder v2 supports pagination.
Added to the volumes table for both admin and project.
Also fix the Cinder REST API to handle pagination (like Glance
REST API).

To test: set 'Items Per Page' in the UI Settings page to a low number.

Co-Authored-By: Cindy Lu <email address hidden>
Co-Authored-By: Timur Sufiev <email address hidden>

Closes-Bug: #1508713

Conflicts:
 openstack_dashboard/test/api_tests/cinder_rest_tests.py

Change-Id: Ib1772d6e6214dc96a09ce32fb4d9f9fb79d161f0