feat(stacks): add a setting to disable the creation of stacks for non-admin users (#3932)

* feat(settings): introduce a setting to prevent non-admin from stack creation

* feat(settings): update stack creation setting

* feat(settings): fail stack creation if user is non admin

* fix(settings): save preventStackCreation setting to state

* feat(stacks): disable add button when settings is enabled

* format(stacks): remove line

* feat(stacks): setting to hide stacks from users

* feat(settings): rename disable stacks setting

* refactor(settings): rename setting to disableStackManagementForRegularUsers

app/docker/components/dockerSidebarContent/dockerSidebarContent.html

@@ -4,7 +4,7 @@
 <li class="sidebar-list" ng-if="!$ctrl.offlineMode" authorization="DockerContainerCreate, PortainerStackCreate">
   <a ui-sref="portainer.templates" ui-sref-active="active">App Templates <span class="menu-icon fa fa-rocket fa-fw"></span></a>
 </li>
-<li class="sidebar-list">
+<li class="sidebar-list" ng-if="!$ctrl.hideStacks">
   <a ui-sref="portainer.stacks" ui-sref-active="active">Stacks <span class="menu-icon fa fa-th-list fa-fw"></span></a>
 </li>
 <li class="sidebar-list" ng-if="$ctrl.swarmManagement">