principal: action class and registry addition

* Adds new registry for access actions.

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
jsonalchemy: cache engine search fix

Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
archiver: initial port to new code structure

* Implements OIS archiver module using bagit.  (addresses #1579)
  (addresses #2258)

Co-authored-by: Jake Cowton <jake.calum.cowton@cern.ch>
Signed-off-by: Jiri Kuncar <jiri.kuncar@cern.ch>
jsonalchemy: fix SmartJson dumps documentation

* Update dumps documentation to describe the new introduced
  parameter.

Signed-off-by: Leonardo Rossi <leonardo.r@cern.ch>