Update the file caching app

- Add view to list available caches.
- Add links to view and purge caches.
- Add permissions.
- Add events.
- Add purge task.
- Remove document image clear link and view.
  This is now handled by the file caching app.

Signed-off-by: Roberto Rosario <roberto.rosario@mayan-edms.com>

mayan/apps/documents/apps.py

@@ -47,7 +47,7 @@ from .handlers import (
     handler_remove_empty_duplicates_lists, handler_scan_duplicates_for
 )
 from .links import (
-    link_clear_image_cache, link_document_clear_transformations,
+    link_document_clear_transformations,
     link_document_clone_transformations, link_document_delete,
     link_document_document_type_edit, link_document_download,
     link_document_duplicates_list, link_document_edit,
@@ -377,7 +377,7 @@ class DocumentsApp(MayanAppConfig):
 
         menu_setup.bind_links(links=(link_document_type_setup,))
         menu_tools.bind_links(
-            links=(link_clear_image_cache, link_duplicated_document_scan)
+            links=(link_duplicated_document_scan,)
         )
 
         # Document type links