login: fix permission issue for guest user

* Fixes a permission issue where a guest user did not have a list of
  permitted restricted collections calculated, causing issue with
  e.g. facets when viewing restricted collections (e.g. restricted to
  role anyuser).
installation: remove library (ZENODO only)

* Removes PyLD due to Python 2.6 requirement.
legacy: dbdump fix

* Fixes imports in dbdump which prevented it from running.

Signed-off-by: Lars Holm Nielsen <lars.holm.nielsen@cern.ch>