feat(endpoints): add the ability to browse offline endpoints (#2253)

* feat(back): saved data in snapshot

* feat(endpoints): adding interceptors to retrieve saved data on offline endpoints

* feat(endpoints): offline dashboard working - need tests on offline views

* refactor(endpoints): interceptors cleaning and saving/loading offline endpoints data in/from localstorage

* feat(endpoints): browsing offline endpoints

* feat(endpoints): removing all the link in offline mode - sidebar not working when switching between off and on modes w/ stateManager logic

* feat(endpoints): endpoint status detection in real time

* fix(endpoints): offline swarm endpoint are not accessible anymore

* fix(endpoints): refactor message + disable offline browsing for an endpoint when no snapshot is available for it

* fix(endpoints): adding timeout and enabling loading bar for offline requests

* fix(endpoints): trying to access a down endpoint wont remove sidebar items if it fails

* feat(endpoints): disable checkboxes on offline views for offline mode

* feat(endpoints): updating endpoint status when detecting a change

* refactor(host): moved offline status panel from engine view to new host view

* fix(endpoints): missing endpoint update on ping from home view

* fix(api): rework EndpointUpdate operation

* refactor(offline): moved endpoint status to EndpointProvider and refactor the status-changed detection

* fix(offline): moved status detection to callback on views -> prevent displaying the offline message when endpoint is back online on view change

* fix(offline): offline message is now displayed online when browsing an offline endpoint

* fix(offline): sidebar updates correctly on endpoint status change

* fix(offline): offline panel not displayed and hidden on online mode

* refactor(offline): rework of OfflineMode management

* refactor(offline): extract information-panel for offlineMode into a component

* refactor(offline): remove redundant binding of informationPanel + endpointStatusInterceptor patter as service

* refactor(interceptors): moved interceptors pattern to service pattern

* feat(stacks): prevent inspection of a stack in offline mode

* feat(host): hide devices/disk panels in offline mode

* feat(host): disable browse action in offline mode

* refactor(home): remove comments

app/docker/components/dockerSidebarContent/docker-sidebar-content.js

@@ -4,6 +4,7 @@ angular.module('portainer.docker').component('dockerSidebarContent', {
     endpointApiVersion: '<',
     swarmManagement: '<',
     standaloneManagement: '<',
-    adminAccess: '<'
+    adminAccess: '<',
+    offlineMode: '<'
   }
 });

app/docker/components/dockerSidebarContent/dockerSidebarContent.html

@@ -1,7 +1,7 @@
 <li class="sidebar-list">
   <a ui-sref="docker.dashboard" ui-sref-active="active">Dashboard <span class="menu-icon fa fa-tachometer-alt fa-fw"></span></a>
 </li>
-<li class="sidebar-list">
+<li class="sidebar-list" ng-if="!$ctrl.offlineMode">
   <a ui-sref="portainer.templates" ui-sref-active="active">App Templates <span class="menu-icon fa fa-rocket fa-fw"></span></a>
 </li>
 <li class="sidebar-list">
@@ -28,7 +28,7 @@
 <li class="sidebar-list" ng-if="$ctrl.endpointApiVersion >= 1.25 && $ctrl.swarmManagement">
   <a ui-sref="docker.secrets" ui-sref-active="active">Secrets <span class="menu-icon fa fa-user-secret fa-fw"></span></a>
 </li>
-<li class="sidebar-list" ng-if="$ctrl.standaloneManagement && $ctrl.adminAccess">
+<li class="sidebar-list" ng-if="$ctrl.standaloneManagement && $ctrl.adminAccess && !$ctrl.offlineMode">
   <a ui-sref="docker.events" ui-sref-active="active">Events <span class="menu-icon fa fa-history fa-fw"></span></a>
 </li>
 <li class="sidebar-list" ng-if="$ctrl.swarmManagement">