Fixes #5664 - Host filters can use taxonomies

Also disables taxonomy filters on resources that do not support them.

Fixes #5221: Adds a helper method to allow a model instance to inquire if the instance is authorized for a particular permission.

Model instances can be asked directly if they are authorized for a particular
permission by, for example, calling 'instance.authorized?(:view_model)'. This...

fixes #5660 - use with_taxonomy_scope for OS media selection

Fixes #5637 - Don't raise lease conflicts when reading ad-hoc DHCP leases

fixes #5553: FiltersHelper#search_path returns an empty string for unrecognized resources

fixes #5680 - quote searches for config groups containing spaces

fixes #4250 - API v2 - add compute profiles

templates - sync from community-templates

fixes #5471 html escape auto-completer values (CVE-2014-0208)

fixes #5612 - use correct permissions for authz in parameters API