Set default value on settings var OPPS_MULTISITE_ADMIN
Check settings OPPS_MULTISITE_ADMIN
Set PostList Container model
Use OPPS_MULTISITE_ADMIN on queryset AdminViewPermission
Set object site on request middleware DynamicSiteMiddleware
set instance attr child_class on View (opps.views.generic.base)
initial refactoring on generic view list, refs #134
remove queryset property, used get_queryset (super)
Add demo containers template list
Set instance attr site on ListView (generic view)
Fix pep8, inport no used