Fix v3 hypervisor extension search action follow REST principles

The original search action as below:
'/os-hypervisors/[filters]/search'

It doesn't follow REST principles.

So change it as:
'/os-hypervisors/search?query=[filters]'

This follow the suggestion from
http://www.slideshare.net/apigee/restful-api-design-second-edition#btnNext at 77 pages.

Partially implements: bp v3-api-extension-versioning

DocImpact

Change-Id: I114868112e0dd719c046853de29df5cfa8dae6b5
Merge "Fix v3 hypervisor extension search action follow REST principles"