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/views/images/images.html

@@ -7,7 +7,7 @@
   <rd-header-content>Images</rd-header-content>
 </rd-header>
 
-<div class="row">
+<div class="row" ng-if="!offlineMode">
   <div class="col-lg-12 col-md-12 col-xs-12">
     <rd-widget>
       <rd-widget-header icon="fa-download" title-text="Pull image ">
@@ -51,7 +51,7 @@
     </rd-widget>
   </div>
 </div>
-
+<information-panel-offline ng-if="offlineMode"></information-panel-offline>
 <div class="row">
   <div class="col-sm-12">
     <images-datatable
@@ -63,6 +63,7 @@
     remove-action="removeAction"
     force-remove-action="confirmRemovalAction"
     export-in-progress="state.exportInProgress"
+    offline-mode="offlineMode"
     ></images-datatable>
   </div>
 </div>