previewer: fix base template for bundles support

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
previewer: initial release of ZIP file plugin

* Adds basic access controll check for record only.

* NOTE Add following line to your configuration to enable this plugin
  `CFG_PREVIEW_PREFERENCE = {'.zip': ['zip']}`  (PR #2321)

Co-authored-by: Jiri Kuncar <jiri.kuncar@cern.ch>
Signed-off-by: Antonios Manaras <antonios.manaras@cern.ch>