Current patch adds two new methods to base class:
* _resolve_all_attributes - for choosing path for resolving, which
depends on type of attribute (base or custom).
* _show_resource - method for resolving base 'show' attribute.
This method should be re-defined for resources, which use clients with
specific implementations of 'show' commands.
New attribute for base class was added - entity, which is used for
resolving 'show' attribute.
Tests for Neutron resources and Server resource were updated
corresponding changes mentioned above.
Hook for stack_resource class is removed in this patch.
Change-Id: I4ee0a53407739e5590c9a8d12bc7c1e84077f4c4
02275f8901