GUI-325: Enable filtering of instances by security group on landing page.
GUI-325: Enable filtering instances by scaling group.
GUI-325: Enable filtering by platform for Images.
GUI-325: Filter IP Addresses by assigned/unassigned flag.
Fix for failing "test_instances_landing_page_json" unit test
Merge pull request #166 from eucalyptus/GUI-325

GUI-325: Landing Page Filters Redux